Question

does the variable ‘var’ gets destroyed before displaying its value?

@echo off
FOR /f "tokens=* delims=" %%G IN ('dir') DO (
set var=%%G
echo %var%
)

Answer 1

This will never work since the reference to %var% is resolved when the body of the loop is parsed. You have to enable delayed variable expansion and use !var! instead:

@ECHO OFF
SETLOCAL EnableDelayedExpansion
FOR /F "tokens=* delims= " %%G IN ('dir') DO (
    SET VAR=%%G
    ECHO !VAR!
)
ENDLOCAL

You can read all about it by type SET /? at a command line 😉