missing top bar

Does this occur for a different user, e.g., Guest ? 

https://support.apple.com/guide/mac-help/set-up-other-users-on-your-mac-mtusr001/mac

Does this occur after starting up in Safe Mode? 

Consider the possibility of a third party software conflict.  EtreCheck can be used to investigate what is installed.  Give it Full Disk Access. You can post the report here. Someone might spot something.

danzooz wrote:

My Mac started to blink on the task bar on the right intermittently. then it would wake up from sleep by itself and I cannot put the password in or use the fingerprint. I then have no choice but to shut it down with the power button. Now I cannot access the top menu bar after shutting down w button. I cannot shut down normally since I cannot access the apple or anything else. Some things cannot be clicked on and the system is dysfunctional without the top bar. How do I get the top bar back and normal so I can shut down normally?

Not sure what is your "task bar" ?

• there is the top menubar
• there is a Touchbar/Control Strip on some Macs
• there is a Dock typically along the bottom

You can always force quit the Mac holding the powerbutton/TouchID for ~6-10 sec.

Reboot as normal and test.

Force shut down:

https://support.apple.com/guide/mac-help/log-out-sleep-wake-restart-or-shut-down-mchlp2522/mac