how do you deactivate or delete an old apple id

If you want to cancel your Apple ID account, you can deactivate it or delete it.

Apple ID - How to deactivate your Apple ID account.    *

All purchases made using an Apple ID are tied to the ID. Delete the ID and you will need to download them using your new ID. There have been posts by people who have contacted Apple Support and they were told that if you delete an ID associated with an email address, you can never reuse the email address for an Apple ID.  Make sure that you sign out of all your devices to avoid issues with apps that use your Apple ID account or iCloud. After your account is deleted, you can't sign out of iCloud or turn off Find My iPhone Activation Lock on your devices. If you forget to sign out, you might not be able to use your device when your account is deleted.

How to delete your Apple ID account.   *  

Apple ID – How to Delete.  -

Delete Apple ID (new).   -

What to do after you change your Apple ID or password - Apple Support 

Hi

You are probably still logged in with that iCloud, which means it is active on your apple device and it might be syncing with Time Machine backup too.

For your own safety, make sure you don't delete what's been backed up on that iClouds Time Machine such as photos, contacts etc.

Log out of the iCloud you want to delete on your device:

Here are the instructions:

https://support.apple.com/en-us/HT208242

After that, you can simply log in to the iCloud threw your browser and permanently delete the iCloud.

But be cautious, I recommend you wait until you see if the iCloud is ready to be deleted.

Good luck.

Here are the instructions for changing Apple ID or password:

https://support.apple.com/en-us/HT204071