Changing Apple ID on Mac

[Aditya_S]

I just got a MacBook Pro shipped to my house however my dad got the package and set it up using his own Apple ID. I've never used macOS so how can I change it to use my own Apple ID. I'm getting texts from my dad's iPhone now on this but I want to sync my phone instead. I've only figured out how to change the App Store but not anything else. How can I change everything to my Apple ID?

 

[hallux]

System Preferences > iCloud > Sign Out

 

[Aditya_S]

System Preferences > iCloud > Sign Out

Just tried that and I signed into my own Apple ID but I'm still getting his texts.

 

[CoastalOR]

Just tried that and I signed into my own Apple ID but I'm still getting his texts.

Change the Messages app Preferences>Accounts. Delete your dads account or disable it and add/enable your account.