My 13” Mac has a different Apple ID than my iPad and iPhone. I’d like to change the Apple ID on my mac so I can utilize apps properly.
Sign out of the old Apple ID on the mac, knowing that you need to keep all the content there. Apps will lose permissions / update while you switch in the proper Apple ID.
Sign in with the proper AppleID so you can share all the data and other apps. They when you have an update, sign back in with the original AppleID (only if you want) to allow updates to the previously purchased apps, but not lose the data syncing from iCloud on the same account on both platforms.