How to add a 2nd Apple ID to my Macbook?

blessedibe0903 wrote:

Is there a way to add a user ID from my Family Shared account to my MacBook?

To what end, may I ask?

Using a second Apple ID for the same user is not a good idea. iCloud services, Contacts, Mail, Calendars App Store purchases, Music and a few other things are tied to your Apple ID. Unless you have a specific legacy reason for using two Apple IDs, it's best no to go there.

However, if you'd like to add a second user account for another user of the same computer, that is easy to do in System Settings > User's & Groups. The second user of that Mac can then log in to iCloud services and App Store and Music accounts using their own Apple ID, separate and apart from other Mac users. They will have secure access to their own documents, files and folders on the Mac and typically cannot access those of other users without password authorization.

D.I. Johnson covered everything I was going to say and added a lot more insight.