My cat is sick and I have no way to take him to the vet! :(

Sorry guys I know this isn't a lerios7/relationship/sex post but my cat is sick and I don't know what to do. I unfortunately just had to pay out over $1000 for a hospital bill for an emergency surgery I had and now have no money to take him to the vet. I just need some opinions on what I can do for him until I get paid and can take him to see the vet. Usually he is a very healthy cat, never throws up hairballs, never has diarrhea, he's a tad overweight, very sweet and happy. He is 3 years old and has been indoors his whole life. The last 3 days he has been randomly throwing up undigested cat food. It looks like it's hardly chewed up, like big chunks. Now I know he is not starving because he is fed from one of those bowls that lets out more food as they eat. He has access to clean water, a clean litter box, and there have been no changes in his diet or at home in general. He still acts like his normal playful self, but he will just be sitting there and randomly puke. I don't know what to do for him until I can afford the vet, I have a 1 year old in the house and I don't want him getting ahold of any cat puke that he may find before I do. Please help if anyone has experienced this before! I would really appreciate it! 🐱