I want to make a movie, but before that, I have couple of questions, and please answer


Is there a way to instantly change face expression?
When I record, Does the needs, and etc. will show up?
If it does show up, is there a way to crop it so it doesnt show
Alternative way, is there a way to hide it

If you have the University expansion then there is a way to change facial expression using the cosmetic surgery career reward. Unless your sim is at career level 6 on whatever career the reward is for (Sorry, I can't remember) then you will have to use a cheat or a hack to make it available. If you press the ctrl and shift buttons at the same time, when you're on the lot you are filming on, then a cheat window will appear and you can type unlockCareerRewards in to it, to unlock all career rewards for whichever sim you are controlling. It worked for me Oh and the needs and etc will show up when you are filming but not on the actual film afterwards.

You can use Tab to go into camera mode and it will hide it but as Kirsty said, the needs will not show up. There isn't really a way to instantly change face expression, I think you mean like happy, disgusted, laughing? No then not really.
The cosmetic surgery is on the Acting career which comes with University.

You can also download a buyable version of Dr. Vu's cosmetic surgeon here. Or use the cheat unlockcareerrewards. You need NL, OFB, and Pets to use unlockcareerrewards according to the Cheats page here.

Ahem... try using,
boolProp testingCheatsEnabled true
in the cheat box, then hold SHIFT and click a sim. At the pie menu, select spawn, then find Sim Modder. When it spawns, it shows up as a unmoving baby. Click it and you can unlock the career rewards there, OR give your sim max career points.
this cheat my result in unwanted gameplay IF you use it on everything else but Sims, unless you know what your doing.