Mac logged me out and can’t get back in
The various options to recover control are quite straightforward to enumerate, and you might have one you think is best to start with:


Boot to recovery and reset the password of one or several admin accounts. (Also, you can use Terminal app in recovery to look if your /User folder is intact before deciding what to do.) - https://support.apple.com/en-us/HT201314
Make a new admin account, then look / repair / backup / reinstate other accounts. - New MacBook had user accounts already; I deleted admin and can&#39;t get back in
Bring another OS to the Mac and backup / fix / diagnose. - https://support.apple.com/en-us/HT202796
Reinstall the OS and see if migration repairs the account - https://support.apple.com/en-us/HT204904
Wipe the Mac and load a backup (easy if you know TimeMachine is ready to go) - https://support.apple.com/en-us/HT204904


Which you choose is mostly up to your skill level and if you know you have a backup - it takes about 10 minutes of time to erase / install then you wait, then it’s 5 minutes to start the restore, and then you wait until it’s done.

The other options can take far less time once you know the steps, but for some take a bit of learning in terminal and could end up with data loss if you don’t just back things up first.