Yes for the blocks.... when you do your form shooting off the wall... use one hand... that will force you to get your elbow under the ball.... but ONCE You shoot the ball and hold your follow thru - putting your hand in the cookie jar (rim) your elbow will end up under the ball and your shot will be straight.
As long as your percentage is good... your form is probably fine...

thanks, and when doing shot of the dribble, Ex:- pretend i do a crossover and then go up for a shot, but am not used to it, and it feels a little umcomfortable, should i start off doing it slowly and then sppeed up or do it game speed right away.

Do it slowly until you can do it well... increase the speed as you get better.

Now i know why i couldn't get any power from the jump shot. I stayed in the air too long and then released it. But I still have to make my form better on the jump shot. Why is that with set shots my form is perfect but with jump shots it feels very different?

Because it is a different type of shot... a set shot is easier... don't have to use your legs as much and you are on the floor for the most part.

so for a few weeks should just shoot jump shots close to the basket and up to the free throw line to get used to it?

Yes, Remember when you first started to dribble with your left hand and do left handed lay ups.... its a little awkward at first. So start in close until you become comfortable with it.

the ball doesn't spin very much when i shoot a jump shot
when i do set shot, ball spins very much

Maybe its because you are trying to get to high? Are you getting your guide hand OFF the ball? Make sure on your follow thru that you put your hand in the cookie jar.

wow it just took me 2 days for my body to get used to it. jump shot feels so natural now.
so far i just shot up to 8 -10 feet. started 2 feet out