Yeah there is some getting used to games where you walk around. I also managed a couple of minutes at a time at first. Now i can play for hours without issue. Also i havent been getting carsick anymore.

Case usually have fans preinstalled that should be fine. Just pay attention to the direction, have tham all blow air front to back. There is usually an arrow indicating which way it moves air.

Run a benchmark after buiding the PC and check temperatures.