1. Click Reports on left sidebar.
2. To explore reports that deal with income to find the one that suits your needs, search on keywords Income or Sales or Profit in the Find Report by Name box.
You're always welcome, @Sokkunthea.
I've got some insights on accessing closing entries in QuickBooks Online.
Here's how to close your books:
On the other hand, if you'd like to run a report for the closing entries made on the account, you can access the account detail for Retained Earnings. This will show you each closing entry with the date and the balance of net income transferred to Retained Earnings.
Here's how to access it from your Chart of Accounts:
Check out this article to know more on what to do with your books every end of the year: Year-end guide for QuickBooks Online.
It's my pleasure to help. Please feel free to comment back if you have other concerns with this matter or QuickBooks. Have a good one!