Hey Madison, welcome to the forums! First of all congratulations on your new card and it’s good to hear that you are feeling better.
I agree with Adam, any additional funds you ad become part of your security deposit, which will only be refunded after you close your account. Some people are ok with this and keep adding money. It’s up to you. I also have a $500 CL and decided this was more than enough. Instead I opened a 2nd secured card which offers graduation, and put all the money I could in there knowing that if used responsibly, it will be refunded after 12-18 months.
I suggest you use your Capital One responsibly for 6 months and then try getting a 2nd one either from Bank of America, Citi or a bank that offers graduation. Who knows, maybe you’ll even qualify for an unsecured card then. CapOne is great to start with, but unfortunately it will not grow with you, so have this in mind.