Found out I have ~$900 sitting in an investment account, what's the best way to use it?

Hello all. Over the weekend, my parents told me about an investment account that my grandfather opened in my name when I was born. There is currently $922.72 in the account. While in the grand scheme of things, I know this isn't that much money, I do want to make sure that I use it the right way.

Some background: I(24), in the past few months, have realized that I have managed to dig myself into a financial hole through irresponsible spending, money management, and credit card debt through my college years. Not a big hole, but a hole nonetheless that is beginning to add pressure and stress to my life. This sub has actually been a huge help in getting me to realize my wrongs, as well as the steps to take to remedy them. Huge thank you to all of the posters and commenters for your advice. Over the past few months, I started using YNAB to budget, as well as finally opened an online savings account with Ally to start building an emergency fund. Budgeting has really helped me get more of a grasp on where my money goes, and just in the short time using the system, I've already found myself a lot less stressed about making bills and payments on time. It has also allowed me to start saving (finally).

Here's my situation at the moment:

I work full time at $11.25/hr. I'm able to pay all my bills, minimum payments, and necessities, with enough to put into savings each week and have a little bit of fun money leftover. I don't think I'm in dire straits.

Debt

• Amazon Store Card - $1289.69 (28% APR)
• Captial One Platinum Card - $297.80 (25.49% APR)
• Debt owed to university - $1268.50 (<2% APR)

Savings

• Ally Savings Account - $100 (the beginnings of my emergency fund, I am putting in $50 out of each weekly paycheck)

I know these numbers are a bit pitiful, but that's why I'm here to fix that! I also have federal student loans, but those aren't even on my radar (I'm on an income based repayment plan and don't currently have to pay anything on them). The debt to the university was incurred when I dropped out. I am on a payment plan and am very very slowly chipping away at it each month. My parents said that the investment account was originally started to help with school costs, but that I am free to do what I wish with it now.

My question is, what would be the best course of action now that I have the knowledge of this account? Do I put it towards the credit card debt to curb the interest, and knock one out completely? Do I top off my emergency fund so I'm able to start more aggressively paying down the debt with a cushion just in case? Do I just leave it to keep growing and continue as is? How does one even withdraw from an investment account in the first place?

Thanks in advance for any advice. This sub really is great.