I ride a mongoose fuzz extreme (yeah...didnt want to spend that much cause I'm just starting out), and the tires are really thick and I wanna get some new tires, my question is, would I have to buy a new rim? I was planning on buying a pair of Maxxis Holy riders
Orbea Enol roadie, Fly Micromachine BMX, Fort Track fixed
Maxxis make some great tyres, and no, you won't need a new rim. Just pop the old tyre off the rim with some tyre levers (NOT a screwdriver) - let the air out first - remove it and the tube, put the tube inside the new tyre, poke the valve though the valve hole in the rim, and work the bead onto the rim, starting at the valve.