Signing off JSA before Uni

Okay, I'm really fed up with the work program, I feel so depressed and stressed out. I come back home in tears. I don't want to go into it that much, but yeah...

I have 7 weeks left till uni starts, and I'd like to sign off now. I already got the place, they're only doing my RPA and my student finance is done, just waiting for the letter.

If I write down that I'll be going to uni for a reason for signing off, will they accept it?
(even though it'll be 7 weeks beforehand)

Will I have to pay them back all the money they gave me?

If they ask what means of support I'll have, can I write down my Mum/Brother?
(she doesn't work but she does get ESA, and my brother does have some student loan that he can lend me)

I really need help thank you