wh is the difference between ought to and should ?

"ought to" is instructive, like an order;

"should" is suggestive, a tone no as strong as "ought to".

Of course, one can politely give an order by saying "You should raise you hand before asking questions". If you say "You ought to raise your hand before asking questions", you are implying there is punishment if the instruction is not followed.

what is the difference between ought to and should ?

ought to - is an order form which means must.
例: You ought to do some warm up before swimming.

should be - is a suggestion & very close to reminding...
例: You should not eat before you go to bed.