Switch AppleID
What is the most effective way to switch my Apple ID from one account to another on my MacBook Air?
MacBook
Change Apple IDs on the computer?
Use the below as a guide of where to sign out/in.
What to do after you change your Apple ID or password - Apple Support
If you create/use a new Apple ID, you will lose access to some of your data and the purchases made with your existing Apple ID. If you want to have 2 Apple IDs on the computer, I suggest going to System Preferences/Users & Groups and create a new user account to use the 2nd ID in.
If I am misunderstanding what you want to do, more information would help.