How to go back to Windows 10 after installing two major versions of Windows 11

Solution 1:

How do I do this?

What you want is impossible. You are only able to uninstall the most recent upgrade. This capability also only exists for 10 days since you performed the upgrade. If the option to rollback your installation, results in you still being on an Insider Preview build of Windows 11, then your only option is to perform a clean install of Windows 10.

Right now I have no way back to Windows 10 because it was replaced with the previous Windows 11 build.

In order to revert back to Windows 10 your only solution to your problem, is to download a current Windows 10 ISO, and revert back to Windows 10 by performing a clean install. The only other option would be to wait until updated device drivers are released that support Windows 11.

Since you are running Windows 11 Insider Preview, having to disable Secure Boot, should not prevent the use of your machine.