How can we use iCloud password for Sierra login account?

Mine got to the last step of downloading and asked for Administrator Password which I didn't know I had. I went through all the passwords I've ever used (had hack attempts) and one of them worked after pressing 'Unlock.' Have no idea why that worked but it is installing now.

Per this link: Mac OSX switch to iCloud password login missing the answer from user Wes Morgan is: "I chatted with Apple Support about this and they said iCloud password login was removed in OS X 10.11.4. It doesn't forcibly remove it from existing accounts, but if you turn it off, you can't turn it back on."

Both options of either do a Change password in the Users and Groups or trying the hack in Terminal won't work anymore

You'll have to manually set your Mac's password ...

I disabled iCloud log in to test something and went to re-enable and had this issue myself. However, after I continued to research, I found this article and it was successful. I am running macOS Sierra 10.12 and it was successful.

https://www.linkedin.com/pulse/reenable-icloud-password-login-os-x-el-capitan-10 114-higher-herman?trk=hp-feed-article-ti…

Part of the problem is that if you are using the Two-Factor authentication option for your iCloud account on apple, which I turned on at the same time the iCloud option disappeared. Apple needs to have a USB biometrics that can offer strong passwords with the swipe of your finger. iTouch ID was working on this but did not finish the project, guessing they got to an impasse on hardware encryption with the security.

Thank you very much