Hi curvyify-gmail-c,
Welcome to the QuickBooks family! QuickBooks Online is a dynamic program for all of your bookkeeping needs. Recording your income and expenses to the correct account ensures your books remain aligned. I'd be glad to assist!
For your reference, here's a detailed guide for recording expenses in QuickBooks Online. When it comes to recording payments, you can enter partial or full payments to your invoices, by following this link. If you're unsure of what accounts to categorize your transactions to, I recommend speaking with an accounting professional. They'll be able to provide you with the best course of action, to ensure a positive outcome on your books. If you don't have an accountant, we can help you locate a ProAdvisor in your local area. In addition, I encourage you to take a look at QuickBooks Online video tutorials, to assist you with becoming more familiar with various processes and navigation.
If you have any other questions please feel free to reach back out. We're always happy to help!