We took a stray cat in 6 years ago and she is now 19 years old,so long as you give food, love and warmth and of course a cat litter tray, then your new family member will be happy.
Your vet can give you details of the PDSA scheme, for free or reduced vet bills, ask him and see if you qualify.
One problem we had for over a year, was after ours had eaten, she would within 15 mins be sick, quite a lot! the vet told us to raise her food dish, we put it on top of an upturned plant pot!, as they get older some cats sprincter? narrow, and as their neck is bent to eat the food builds up, and as they then lift their neck, there is a surge of food trying to go down and of course it cannot so it all comes back up....since the plant pot she has never been sick again ! Gosh I have gone on and on....sorry!
Good luck.