"You only go to university 3 days a week"
Might be true that some courses are very light on the contact hours, but I definitely wouldn't count on that.
Also, what maintenance loan are you eligible for? You might find that after your dad fills out the form you're eligible for the full maintenance loan and won't need your dads support. If push comes to shove, you might have to hang on by the skin of your teeth with a mixture of whatever maintenance loan you're eligible for, scholarships available from the uni or private companies, a part time job, interest free overdraft, and if possible uni hardship funds (although as a plate-glass Warwick doesn't have the biggest endowment so it might be difficult to access these).
I wish I could help you with your family and Warwick specific stuff, but unfortunately I'm a prospective Southampton student and non-Muslim, so I can't really help. I can give you my condolences though, it really sucks that your dad thinks so little of your faith in Islam that he thinks that a bunch of posh white kids will turn you against it. I can't even comprehend how insulting that must be.