Do you have to hold a postion?

I am not familiar but when you power lift bench, squat, etc.
Do you have to squat what 90 degrees with your quad and calf? or go parallel? How far do you have to go down? Do you have to hold that position?
Same with bench press does the bar have to touch your chest?

I think in Squats, you have to go all the way down - past parallel.

Bench press I think it might be a penalty if it touches the chest ??

I could be wrong (and probably are about bench), but this is what I recall from watching ESPN2 shows a long time ago.

Rules vary with federations. For the most part the hip joint has to go below the top of the knee (below parallel) for a good squat. On the bench you have to come down and stop on your chest, usually until a
"press" command is given, which usually doesn't come until there is a dramatic pause.

You can usually pull up a rule book for a given federation on their website,APF,WPC,WPO, and god forbid even the USAPL.

The bar has to touch the chest in all feds.

HP

most groups are pretty consistent with these rules:
on squat it may be defined as hip dropping below knee although I've always seen top of thigh parallel with floor- no need to hold it, break parallel and return. (the command to squat will be given at the top of the movement, after stepping out with weight and remaining motionless)
For B.P., one must lower weight to chest, pause until lift command is given ( time can vary with head officials but generally it is until all motion has ceased) extend to lockout and rack.
There is a push right now to change BP to the squat style in that official would command lift to begin and leave it to the lifter to make adequate pause. Most fear this may allow whites on too many "touch and goes" so we'll see what happens.

Hope it helps