How to exit from Commad prompt window?

Using EXIT will stop execution of a batch file and return control to the command processor (or, with NT's /B switch, to the calling batch file) immediately.

Using EXIT /B will stop execution of a batch file or subroutine and return control to the command processor or to the calling batch file or code immediately.
EXIT /B is available in Windows 2000 and later versions' CMD.EXE only.
If followed by an integer number the code will return an exit code or ERRORLEVEL equal to that number

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