Win10 Education; Files appear to be encrypted, but not through bitlocker

I am currently faced with the following issue: When booting the PC I boot into a "automatic repair could not fix your PC" screen. trying to run chkdsk or similar commands through the in this menu available X: cmd tells me that the disk is in read-only. read-only can not be cleared through diskpart. I have also tried running cipher, in which case it tells me that it does not know a command by the name of "cipher". Trying to run the get-childitem Powershell command through the cmd does not work either, it tells me that there is no such command as "Powershell.exe" or "Powershell". Trying to run U