Can anyone please help me with the fromula to figure out cash received from customers or fees earned. I am very new to accounting and have an assignment due that I need to work and I am stuck. I can't figure out the net income to solve other problems without the fees earned. Thanks!

There isn't any "formula" to figure out how much you earned or how much you received from customers. I would like to point out that how much you received is not the same thing as what you earned. Since you're referring to net income, I'll assume you're concerned with the revenues. So leave cash receipts out of it because that's not the same thing.

Anyway, the earnings is whatever the account added up to by the end of the accounting period. The only "formula" is that you keep adding new entries to it until you're done at the end of the period. And then you pull that balance out of that account, and that's your revenues.

Net income is revenues less expenses, but the revenues and expenses both are coming from the balances in those accounts, and not calculated with some formula. And those balances are coming from you doing transactions, meaning of course it's different every time.