Salam Fahad
The home office only allows 20 hours of work per week on a student visa which is enough to support your living in the UK but not near enough to save money towards your fees. They are pretty strict these days. Previously students used to work more than 20 hours without much problem but now they are demanding your national insurance number when you renew your UK visa.

They can easily find out from it if you have worked for more than 20 hours which inturn creates trouble, even deportation.

Normally IELTS is enough to get admission in a UK university. There are now many universities sending their representatives abroad to lure students to join their universities with money off of your fees. In some cases, I have known, there is even a 50% off the fees. So you look out for such events.

Hope this helps.