Q: how to reset apple ID?

You can't reset your Apple ID. You can change the Apple ID if you get a new email address and you can create a new Apple ID. You can't reset an Apple ID. If your phone was previously owned, that is the Apple ID that you need to remove the activation lock. If the previous owner, can not be contacted, or does not remember the ID, there is nothing that you can do to unlock the phone.

Turn off Find My iPhone Activation Lock - Apple Support