Q: How do you enable your apple ID? Mine is disabled even though I never disabled it

Depends upon why it's been disabled. If for security reasons then resetting the password might fix it : If your Apple ID has been locked - Apple Support

You might then need to log out and back into the account wherever you're using it : What to do after you change your Apple ID email address or password - Apple Support

If that doesn't fix it then contact iTunes Support : https://www.apple.com/emea/support/itunes/contact.html