Message on computer - won't go away

Hi there, Summer!

Thanks for visiting the Apple Support Communities. I understand from your post that there is a message appearing on your Mac prompting you to select a checkbox to complete the installation, but you're not sure what it's coming from. I'm happy to help!

The message you're seeing is likely due to third-party software you've installed. If you're not sure which software is bringing the message up, I have a few steps you can use to try to get rid of the popup. Try these in order, checking for the message after each step and stopping when the issue is resolved:

1. Quit any open apps: Quit apps on Mac - Apple Support, then restart your Mac: How to turn your Mac on or off - Apple Support.
2. Start your Mac in safe mode: Use safe mode to isolate issues with your Mac - Apple Support. Safe mode will run a few checks and make repairs where it can during boot up, so it may take a little longer to start up than usual. The checks and repairs may also resolve the issue on their own.
3. Check what apps are set to automatically start when you log into your Mac: Open items automatically when you log in on Mac - Apple Support. If you see an app you don't recognize, remove it from the list, and delete it from the Mac: How to delete apps on your Mac - Apple Support.
4. See if the message appears in a new, test user: How to test an issue in another user account on your Mac - Apple Support.

Don't hesitate to respond back if you still need assistance.

Best!