$ perl -E 'for( my $i=0; $i<10; $i++ ){say "Inside loop: $i";} say "Ou
+tside loop: $i";'
Inside loop: 0
Inside loop: 1
Inside loop: 2
Inside loop: 3
Inside loop: 4
Inside loop: 5
Inside loop: 6
Inside loop: 7
Inside loop: 8
Inside loop: 9
Outside loop:
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...
Inside loop: 9
Use of uninitialized value $i in concatenation (.) or string at -e lin
+e 1.
Outside loop:
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I want to restrict the scope of number.

It's not clear to me, but it seems possible you're actually asking "I want to restrict the scope of the $number scalar." If that's the case, then one way is to establish an independent scope  { ... } for the variable:

c:\@Work\Perl\monks>perl -wMstrict -le
"my $number = 42;
 print '$number before independent scope == ', $number;
 ;;
 { my $number = 8;
   print '$number in independent scope == ', $number++ for 1 .. 5;
   }
 ;;
 print '$number after independent scope == ', $number;
"
$number before independent scope == 42
$number in independent scope == 8
$number in independent scope == 9
$number in independent scope == 10
$number in independent scope == 11
$number in independent scope == 12
$number after independent scope == 42
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Update: Discussions of scoping can be found throughout perlsyn and among the Tutorials in the Variables and Scoping section.

Here if i use my keyword for number its scope is also available in other functions. I want to restrict the scope of number.

What other functions???