Dear My system gets into the trouble in windows 10

Question

now I want to write the command line statement to retrieve the registry 

but the slash \ is replaced by # sign I check the internet and one of the reference there says you need to change the language from English UK to English US , but i am unable to login into my system as it  is crashed and i am trying to repair it by repairing the registry how to change the language by either way bios or command line , as i am unable to login into the system and then change it from the control panel .