restrictions passcode

You'll need to erase your device and set it up as new to remove the Restrictions passcode.

Use Screen Time to prevent purchasing on your iPhone, iPad, or iPod touch - Apple Support

"If you can't remember a restrictions passcode that you set on a previous version of iOS, or you forgot your Screen Time passcode, you need to erase your device, then set it up as a new device to remove the passcode. Restoring your device from a backup won't remove your passcode."

No. If there were a workaround, the idea of having a restrictions passcode would be useless.

You must erase the iPad and set it up as new. Do not restore a backup as that will re-introduce the forgotten code.