Can't shutdown using the apple menu

Go to the Force Quit menu, but don't force quit anything, try first to normal quit all running applications.

If the problem persists, then from the Force Quit menu try restarting the Finder.

If the problem still persists, hold the power button until the computer shuts down. Then try these things, check after each to see if you can shut down normally:

restart in Safe Mode https://support.apple.com/en-in/guide/mac-help/mh21245/mac This may take 20 minutes (or more)

https://www.macworld.com/article/2881177/how-to-reset-a-macs-nvram-pram-and-smc.html reset NVRAM, and SMC

Hey there!

I’ve seen this a number of times. Symptoms change on each OS release, but all are basically universal. Besides the steps you’ve already tried:

Does this happen when ALL apps are closed? And if Finder is relaunched (As said)? Or can you even get the Force Quit menu to open?

If there are apps running in the background preventing a shut down, I may try removing the Login Items and restarting to test:

System Preferences > Users and Groups > Login Items. Highlight each item and press the “-“ sign below to remove each. Restart and try again.

Otherwise another good test would be in another user, as I know Safe Boot won’t load and First Aid was already done:

https://support.apple.com/sl-si/guide/mac-help/mtusr001/mac

It May help to know if this is happening across the whole system or just in your user account, as some troubleshooting may not be needed or effective. This will help to narrow the cause down.

Likewise as Steve626 said, a possible firmware reset could even fix it! They only take a minute and may fix many related problems, so I would try those first! (SMC/PRAM), etc.

Hope all goes okay! Likewise, if you do need to boot to safe mode but can’t, you can use Terminal to do so, but shouldn’t be necessary, if it works fine in safe mode, then app uninstalled are the way to go, but if you can’t peg it to one, I may know where to go to remove them and their components.

As said before, in any case, it’s a good idea to backup your data, as, as always, sometimes the system just needs to be reset if all else fails, so better safe than sorry, but hope this is a quick fix for you, and one of those steps leads you to a suspect and resolution! Cheers!

Backup using Time Machine:

https://support.apple.com/en-us/HT201250

Do you have (or are you able to make) a good backup or copy of all your files (including Apple Mail files which are in your use Library folder)? Time Machine or a "clone" would be best, or if possible one of each.

Have you tried to reset NVRAM and SMC?

https://www.macworld.com/article/2881177/how-to-reset-a-macs-nvram-pram-and-smc.html reset NVRAM, and SMC

I think the next thing to try, assuming you can make that backup, is to boot in Recovery again and reinstall the operating system. Choose the option that does NOT reformat (erase) the disk. If that also fails, again, assuming you have a reliable backup, you can then select the option to erase the disk and reinstall the OS, this is the most severe option, after which you would need to migrate back your user files only (no applications or settings) from the backup. Then, if the computer is working properly, you would proceed to reinstall your applications, restore settings, etc. This is easier to do than it might sound, but I am hoping one of the less invasive options works and the erase/reinstall is not necessary.

Can you boot into recovery CMD-R when booting and then select Disk Utility to run first aid on your boot drive?