Activation I can’t log in because I don’t remember my password to unlock activation lock

You need to get the person who put the activation lock on it to follow the steps here:

https://support.apple.com/en-us/HT201351

If they can't remember their credentials, they can go here and follow these instructions:

https://support.apple.com/en-us/HT201354

If they refuse or still cannot release the lock, you may as well turn it in to be recycled, for it is thus a brick.

Activation Lock

If you purchased, were given, or found a device second-hand, then it is useless without the Apple ID and password to which it is locked. If you don't have it, can't remember it or cannot get it, then the device is useless to you. If you are the original owner then take the device, a copy of your purchase receipt and identity proof to an Apple retailer where they may be able to assist you. This is also true for devices of deceased persons. You will need a certified copy of the death certificate, proof that you are the heir, proof of ID, and proof that the deceased was the legal owner. Note that getting around the Find My Phone activation lock may not be possible.

     Find My iPhone Activation Lock

     If you can't activate your iPhone - Apple Support

If you have an Apple Watch please see; About Activation Lock on your Apple Watch - Apple Support.