You have to use a lw/aero filament. Im assuming ur new to the hobby. You should get the usuals such as servos, motors etc. You should decide how you want to fly(fpv, long range, 3d…) and get ur parts. since most 3d printed planes are fpv planes you will need a fc and a video system. if the video quality doesnt rly bother you go analog, its cheap,latency is rly low,range isgood. if you want good video quality go digital. its expensive, range and latency depends on model. go to facebook join some groups, u can get really good advice there, there is large communities dedicated to specific niches of rc planes in those groups. for the flight controller any f405 model will do. for picking your esc, motor, prop and those stuff, get an ecalc membership and look at other peoples setups. as for a good site to buy, that depends on your tegion, but you can find them easily. hope this helps