If you only stay 3 nights but booked for 7 days can you get a refund for the remaking days

Don't pay up front

Yes you can the only thing is it can take 7 to 10 days to show up in your account

Only if you don't pay upfront.once you pay for the week,that room is yours for the week.if you leave or get kicked out,you lose your money

Yes , I would not recommend staying there.

You should. Just call the hotel and talk to them