Simplicity may help you a little. Changing your behavior and paying off your debts will help your credit score

Changing banks won't really do anything. That's sort of like saying eating your dinner in the basement instead of the kitchen will help you lose weight

Your biggest issue is not how many bank accounts you have, it's the fact that you are not making enough money to pay your credit card off.

Ideas to research:

transferring CC to a 0% balance introductory offer card, if you can find one and get approved

forbearance for student loans for a year until you can clear the credit card debt

Not sure if you qualify, but you could look into Michigan energy assistance program https://www.michigan.gov/mpsc/consumer/energy-assistance

getting a roommate

moving back in with parents, if possible

picking up extra hours or a side gig and putting all that money toward the CC debt