Let me begin by apologising because this will more than likely be a repost.
I am looking into buying my first mountain bike and have no clue what to look for. I know that I want a bike with suspension on the front and back but dont know what brands are decent. Could you give me suggestions on which bikes would be best to start out with, what sites to look for used bikes, ect?

What is your budget? I'm new to mountain biking too, but from what I've read around here, full suspension bikes are $$$$. I think you're looking at at Least $1000 for entry level of decent full suspension. Nice ones closer to $3-5000. And unless you're riding some pretty serious stuff, you don't need rear suspension.

I was thinking $1000-$1500 Ive ridden a couple of my friends bikes and one had hydraulic brakes and the other didnt and really like the hydraulic. I live in north Texas so almost anything around here is going to be pretty tame but my friends who are talking me into mtn biking are already looking into trips to Colorado once I get pretty used to riding that is why I decided not to go with a hard tail.

See if you can find somewhere where you can test ride something like this: https://www.giant-bicycles.com/en-us/...x4/7321/44098/
Giant gives you a pretty good amount of bang for your buck, and they offer a full suspension bike in your price range (Trek and Specialized's entry level models are a couple of hundred dollars more). You get Shimano's entry level hydraulics on there. And while the drivetrain isn't great (Alivio/Deore mix), the fork (RockShox Tora) isn't bad at all. 5 inches of travel, so it's considered an all-around trail bike.

Also make sure you check out the second tier companies, like Jamis, Rocky Mountain, Kona, GT, Haro, and the like, because they often offer great value for less money than you'd pay for something from one of the big boys or for a boutique bike.

And no matter what, test out the bike before you buy. No sense dropping that kind of money on a bike that doesn't fit right.

Yeah I actually had my eye on that bike and am planning on test riding it but the closest bike shop is an hours drive for me. The only thing is I was warned about the components on it but have also read that as a beginner I probably shouldnt worry about that as much.. any truth to this? Also, what are some good sites to look at for used bikes?

The components are fine. They're not top of the line by any stretch of the imagination, but they will do their job. The only catch is that they will need adjustment more often than a more expensive groupset.

Check Craigslist for used bikes. The issues with Craigslist for beginners are that beginners often don't know how to size a bike properly (I *thought* the first bike I bought off Craigslist fit me well, but the more bikes I rode, the more I realized that it did not), making sure it's in good condition and there's nothing wrong with it, and making sure you're getting a good deal. If your friends are really into bikes, bring them along to help you.