bitcoin core – How to import legacy wallet from private keys

The private key is in Base58 format using the uncompressed public key. The private key is a mini key consisting of 22 characters. I bought Bitcoin in February 2009 and forgot where I invested it, but I found out it was Bitcoin 2 years ago and recovered my private key 2 months ago.

It’s so old that there are file compatibility issues, etc.

A trusted family member will help me set it up, but I’d like your advice as a guide to make sure he’s doing the right thing.

Could you please help give him step by step guidance on what to do?

The wallet was last accessed in late 2009.