Can i add footnotes/comments to budget?

I'm delighted to have you here today.

If you're referring to adding notes/comments when creating a budget, know the option isn't available. However, if you're running a report for a budget, you can add notes to the budget report. Now if you wish to continue, I'll gladly write down the steps to get you going:

1. Access your QuickBooks Online company.
2. On the left navigational bar, go to the Reports tab.
3. In the Search bar, enter Budget as your keyword.
4. Select the report.
5. Below the Budget field, click Add notes.
6. Enter your comment or notes below the data.
7. Once done, click the Save customisation button.
8. Fill out the necessary information, and then click Save.

For visual reference, see the screenshot that I've attached.

Moreover, here's an article to help you manage existing budget inside QBO: Create budgets in QuickBooks Online.

I'll be happy to help you again if you have any additional QuickBooks-related queries or need assistance accomplishing goals inside the program. Please don't hesitate to leave a comment below. I'll be here, ready to help you out again. Stay safe, and have a nice day!