Can I downgrade my iPad from iPadOS 18 to the previous version?

Rolling-back to an earlier version of iOS/iPadOS is not possible.

All System Updates are digitally signed by Apple - and can only be installed whilst the digital signatures remain valid. After release of a new iOS/iPadOS version, the immediately preceding version continues to be digitally signed by Apple - however, usually within a few days, Apple will revoke the digital certificate with which the earlier version is signed.

Apple stop singing downgrades iPadOS 17 you can’t downgrade to old iPadOS

Their is not a way to downgrade iPadOS if you factory reset the ipad it will go back to the iPadOS it was originally on