Can you mark an invoice paid?

Yes, you can definitely do that, Jena. 

Here's how to mark an invoice as paid:

1. Go to Get paid, then select Invoices.
2. Find the invoice that you want to record as paid.
3. Under the Action column, select Record payment.
   
4. Choose the account for the Deposited to dropdown.
5. Click Save.

If you want to process payments in QuickBooks, you can set up QuickBooks Payments.

We're always around if you need help with invoices in QuickBooks Solopreneur. Feel free to hit the Reply button below.

@brenickjena 

If you don't want the invoice sale to affect your books, create a credit memo with the same product(s) and apply it to the invoice.  If you need the sale from the invoice to show in your books, then you're going to have another offsetting entry (this is double-entry accounting after all).  If you can provide more details, then we can determine what the proper offsetting account is.