For such kind of activity always follow chomp. It removes new line from the string, right now without chomp your string 1 = Mahesh\n chomp will simply make it Mahesh

print "Enter a word: \n";
chomp($string1 = <STDIN>);
$string2 = 'Mahesh';

if($string1 eq $string2){
    print "Match \n";
    }
    else {
    print "Does not match \n";
    }
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