Please can I re-create a recovery key for my 1stGEN iPAD

If your AppleID is still using 2 step verification -> Two-step verification for Apple ID - Apple Support you May be able to generate a new recovery key if you have a trusted device still linked to that AppleID.

If you’ve updated your AppleID to 2 factor authentication -> Two-factor authentication for Apple ID - Apple Support then the recovery key system no longer applies to your AppleID. As long as you have a trusted device available or a trusted backup phone number, you can get a 2FA code. On an older device like your iPad you would enter the 6 digit 2FA code right after your AppleID password - e.g. password123456

The original recovery key mechanism has long ago been deprecated and is no longer used. When the original recovery key was generated, you will have been altered to the need to record (and keep safe) the recovery key - as regeneration would not be possible.

Your first generation iPad is obsolete. Even if you are able to recovery your recovery key, you will not be able to find or download any compatible Apps from the Apple App Store.

Sorry, this is clearly not the news that you were hoping to learn.