Thanks for dropping by the Community, @sherry27.
In QuickBooks Online (QBO), to enlarge the print on checks, you can use the scale on the Print settings to adjust them. Here's how to do it:
- Open the specific check, then click the Print check option at the bottom.
- Select the Print icon at the top right to open the settings.
- Tick the More settings drop-down.
- Choose Custom in the Scale field, then adjust the size by clicking the Up or Down arrow.
- Once done, hit Print to complete.

You can also print partial pages and voucher checks in QBO, visit this article for more information: Print checks.
Please leave a comment below if you have any additional questions or concerns. I'm always here to answer them. Have a great day!