So I just got my first flat tire last weekend and my trip could have continued if I have an Inner tube by me. What inner tubes would you guys preffer. And do tires such as a brandnew Gatorskin include an innertube with it? TIA

Tires generally do not include inner tubes.

As far as which inner tube to get... the most important part is that it fits.
You'll want to make sure that the valve type is correct for the hole in your rim (presta or schrader). Also that the valve is long enough, if you have rims with a deep cross-section; it's very embarrassing to be the person whose spare tube didn't have a long enough valve to stick out of the inside of the rim.
The tube should be for the right wheel diameter. Tubes are very stretchy, so there's some wiggle room; tubes for 700c wheels will fit fine in 27" wheels, for instance, and are sometimes even labelled for both.
The tube should more or less match the tire width, but again, tubes are very stretchy so there's a range. Most tubes are labelled for a range of compatible widths, i.e. "25-32". I'd caution that erring high on the tube width demands extra-careful tube installation, making sure to not pinch the bigger tube between tire and rim while installing the tire. Some people prefer to err low with tube width, because it makes the tube lighter and more compact and easier to install.

Tubes with thick walls and/or sealant/slime can improve puncture resistance, but may weigh more and make the ride slower and harsher. (This is also true of puncture resistance built into tires.)
Super-thin tubes and latex tubes are light and ride very nicely, but you need to be extra-careful with installation, and they lose air pressure faster (but you should be checking tire pressure before every ride anyway ).

Always ride with the tools you need to fix a flat.

Yeah, if you have one of those bags that mounts under your seat you can have a spare tube and other things in there that will help you self-recover during a ride.

A few weeks ago I hit a 2" curb going a little too fast and pinch-flatted. Pulled over and unmounted the wheel, and pulled the tire off. An old guy stopped to see if I was OK. I then pulled a spare tube out of my bag and proceeded to install it, put the tire back on, etc. He seemed dumbfounded, and asked "You're putting a new tube in?" I was kind of shocked. Apparently this guy rides his crossover bike around the neighborhood with his wife but probably has someone do all his bike maintenance, and it never occurred to him that someone might actually replace a tube on the side of the road. I couldn't believe it. He asked if I had all the tools I need. Yup, fingers all there. Good to go.

Gatorskins don't come with tubes, just like any other tire won't come with a tube. You can buy tubes cheaply almost anywhere, but in multi-packs on places like Amazon and whatnt you can get them pretty darn cheap. It's a good idea to always have a tube, and a patch kit in your little tool bag under the seat. The tube is for the first flat. The patch kit is for if it's a really, really bad day and there's a second flat. I've got a tiny little bike pump mounted alongside my water bottle, but really that's plan B. A CO2 cartridge inflater is plan A. It's just much more convenient.

Btw, I hate Gatorskins. They do resist flats better than average, but I don't flat very often anyway, and Gatorskins feel dead and lifeless to me, and I've ridden them enough to wear out several Gatorskins before. I won't use them again unless I'm invited to compete in the inaugural Tour de Broken Glass Classic alley race.

This. For century rides (Toronto to Niagara Falls) we recommend folks bring along 2 tubes but always bring a spare with you along with wrenches and some type of inflator (CO2 or pump). Never know where you'll flat.

I don't sweat tube brand much and have had good luck with MEC's house brand cheapie the last few years. If I can get conti tubes for not too severe premium i'll get those but i'm a big fan of the conti gp4000.

They're pretty much commodities so I just get whatever's on sale. Like the others said, the most important thing is to get ones that fit:

1) the circumference of your wheel (700c vs. 26in, for example)
2) the width of your tire (23mm vs. 38mm, for example)
3) the valve type (presta v. shrader)
4) the valve length (they have to be long enough to clear the rim so you can get the pump head on)

So different wheels for different bikes require different tubes. If in doubt, ask at your friendly neighborhood bike shop.

I got stock 23mm tire in my bike can I change it freely with a larger one without changing something in my wheels? What size would you guys preffer and what tire will it be? I am just new in road cycling btw.

What do you mean by change it freely with a larger one? Do you mean mounting larger tires? The size of the tire is going to be limited by the frame and fork of your bike. Without knowing what kind of bike you have, it's difficult to say.

That said, you can probably mount 25mm tires.

You'll have to look at your bike to see how much room there is outside of your tires. The two main places to check will be up at the top of the fork, and in the rear of the bike at the chainstays before they meet up with the bottom bracket. If you have some room around your 23mm tires then you should be able to put at least 25mm tires, and possibly larger. My current bike has barely enough room for a 28mm tire that actually inflates up to 30.5mm in width in the rear, and in the front I'm limited to a 25mm tire that actually inflates to 28mm of real width.

The nominal tire size isn't necessarily going to be what width the tire is once it's inflated. Things that can affect this width include the model of the tire, and the width of the rim itself. If your rims are very narrow than the tire won't be as wide once it's inflated as it will be if your rims are nice and wide.

Personally I'd say put the widest tires on your bike that they will fit, within reason. If you can fit 28mm then give them a try.

As far as model differences, two tires I have a lot of experience with are Gatorskins (yuck!) and Grand Prix 4000s from Continental. The Gatorskins on my rims inflate to a real width that's fairly close to the nominal tire width, ie: 25mm Gatorskins are just a little wider than 25mm on my bike. The Grand Prix 4000s, however, inflate to a much wider real width than the nominal tire width. On my bike 25mm GP4000s inflate to more like 28mm, and the 28mm GP4000s are over 30mm.

I have far more experience with these two models than with any other models over the last few years. Gatorskins reduce your likelihood of getting a flat during a ride, but they feel lifeless and dead to me, and suck more energy from you just to roll them. The Grand Prix 4000s aren't as well protected as Gatorskins from flats, but they do quite well and I don't get flats very often (every couple of months mainly), and usually when I do it's my own damn fault (pinch flat by hitting a small curb going too fast/too direct an angle, etc.). The Grand Prix 4000s feel much nicer and don't suck as much energy. Going from Gatorskins to Grand Prix 4000s is sort of a night vs. day experience on my bike.

The Grand Prix 4 Season is a nice compromise between the GP4000 and Gatorskins, although in the end I prefer the GP4000. As far as tube brands, I don't really sweat it too much. I usually look for the least expensive ones I can find. I picked up some earlier this week for $1.96 each - shipping included. I also don't lose sleep over the tube width. The tubes that are on my bike now are for 18-25mm tires, but I'm running them on 28mm tires without any problems. Although to be clear you probably wouldn't be able to run a 28mm tube on a 23mm tire.