Sick male cat

I have a 7 year old Maine coon that isn't feeling well. This morning after he ate his morning wet food he vomited and hasn't been able to keep any food or water down all day. He hasn't urinated at all. I don't have the money to take him to a 24 hour vet. Is there anything I can do until I get him to a vet tomorrow?

Have you seen him straining to try to urinate?  The concern with a male cat is a blockage.  If he is blocked it is an emergency situation.

With his vomiting everything there really isn't anything that you can do at home.  It may be there isn't anything going in so nothing to come out.

He goes to use the litter box but doesn't stay in long.

If he is licking heavily at his genitals after coming out of the litter box with no pee it is an emergency situation.

I took him to a 24 hour vet. He said that he's blocked and they are keeping him for 2-3 days.

So glad you got him in to the vet!