I paid all my credit cards off. All I have on my credit is a 20k car note and medical bills in default. About 7k total. If I pay this (the medical bills)will my score go up? Also I have a few cards I know I can get increases on. Is it always a good idea to accept increases?

how does this shyt wrk?? I took a personal finance class bike in hs dat went over this and interests, checks, leasing, bankruptcy etc. but i forgot most of what i learned. I need yall to break this shyt down to me, 
