Follow the steps in this article to see if they help.
https://www.itpro.co.uk/operating-systems/34614/how-to-fix-the-windows-10-start-menu-if-its-frozenRun the dism /online /cleanup-image /restorehealth before the sfc /scannow if you have to proceed to that one.
You can copy & paste the long commands in the article to the command prompt to eliminate any typos.
You could perform a chkdsk /r to ensure your HDD is okay but given these errors follow a fresh install of Win 10 then it's possible the install you are using could be corrupt.
You can create a new install USB after reading
https://www.microsoft.com/en-gb/software-download/windows10This defaults to English but you can select the German version after unchecking the box for the recommended version and using the dropdown.