Credit scores

Is it normal to have a credit score of 660 at 24 years old with about 3 years of credit and 100% payment background? I don’t have any hard credit lines. I have a student loan I’m paying off, and a few credit cards. I own my vehicle so I don’t have that for credit but I am wanting a credit score of 700+ if possible for my age. What are some things I can do? I’ve been paying bills with my credit cards and paying them off each bill cycle to help but I’m wondering if there’s anything else I can do? I have 2 hospital bills on there as well that I haven’t started paying towards.