Usually it helps to delete the file “kritarc”, when you start Krita again the error should be fixed, because Krita will recreate the file. The unfortunate thing is that you lose the settings you have made to Krita so far and have to set Krita up again. There may be other ways to do this, but I am not aware of any others.
You can find this file in your user path, right at the end of the directory “c:\Users\YOUR WINDOWS USERNAME\AppData\Local\”, where you have to replace “YOUR WINDOWS USERNAME” with your Windows username.
If you can’t find the path you will have to enable the hidden files and folders display which is disabled by default on Windows, a description how to achieve this can be found here.
Michelist
Edit: Please excuse my rudeness @sevi_emin. Welcome to the forum! 