What do you mean by nightlife? How religious of a Muslim are you? I think with every University, there will defo be quite a lot of people that don't drink if that's what you're wondering so you could hang out with them?
Depends if you'd want to go to a club etc
Also it's quite hard to generally assume the UK. It depends on the University, the diversity, the % of international students, religious backgrounds etc
I may not be right but personally I think it would be easier to fit in as a POC in a University in London like Kings than Exeter