Hi i am preparing for tower take over and this is my secound year of vex comp and I was trying to find out if I put a fpv camera that worked at differnt frequency than the robot if I could put the screen on the controller and use that to help line up a claw or something to pick up the blocks
No, this would not be legal. Per <R12>, components not made by VEX (or otherwise allowed under rules like <R7>) can only be added if they do not “affect Robot performance in any significant way or affect the outcome of the Match”.
Using a wireless-transmitting camera to line up the robot would definitely qualify as “affect[ing] robot performance”, and thus this strategy is not allowed.
The vision sensor - a legal component - would also be capable of doing this, but using its wireless-transmission capability is prohibited by <R13>.