Your RAM usage in the screenshots looks normal, Windows 11 is very resource hungry, by default the operating system alone may use 4GB+ of RAM, and in Task Manager, you will not see the amount of RAM used by Windows, just the processes and apps running on your PC.
Restart (not shut down) your PC to flush out your RAM.
Do not start any apps.
Open Task Manager.
Select the Performance tab.
Click Memory on the left.
Please provide a screenshot of that Performance tab.