Debt issue

Hi, not asking for money just advice I (25F) am in a bit of debt and recently got a derogatory account notice from capital once as I’ve neglected to pay on time.
For some context, I work 3-5 shifts a week as a server and make about 50-100 in tips a night depending on the day. I probably make about 2 an hour. I apply for jobs everyday, but sadly I’m limited due to not having my ged, I have one ged test left to take and I’m currently in community college, I plan to transfer to university in the spring. I have a lot of personal bills, like my car for example is 700 a month. I live at home and do receive some help paying bills occasionally. I am trying my hardest, I don’t know where to begin with a budget plan as my hours and pay are so inconsistent. I know I need a second job but I just got hired and my boss is against me working two jobs so I’m “readily available”. This all being said literally every bill in my name is paid on time except the capital one which I just kept putting off and didn’t have the extra funds for (i definitely did but I didn’t think about it at the time)
I don’t know what they mean by derogatory account honestly and am super scared I’m going to get in legal trouble for owing them money.
I’m not asking for money or how to make more but can I better budget my money, when I make so little. Usually I get my tips after my shift and immediately need gas or it goes to another bill (ex phone)
I really don’t spend too much on myself but I do like to get myself things every once in a while so I’m not completely miserable.
I have applied for all state help and so far all declined.