That isn't VB.
It's DOS / CMD commands as used inside a batch file.
SET lest you manipulate Environment Variables:
Batch files - The SET command[
^]
REM is a comment.
ECHO displays text to the user:
Help for all Windows 2000 SP 4 commands[
^]
CSCRIPT runs a script file:
cscript | Microsoft Docs[
^] - in this case it runs a VBS file called
INPUT.VBS
from the
TEMP
folder, and passes it two Environment Variables that were supplied when teh original batch file was executed, but with any quotes around them removed.