Neither your code nor your description really tell us anything useful about what you are trying to achieve. Something as simple as:

use strict;
use warnings;

/^output/ and print while <DATA>;


__DATA__
hfkjd
process jhk
start
begin
output1
output2
end process
scrap
hkl
process khfk
shoot
hooter
begin
output3
end process
[download]

does what you ask for. But that sure doesn't seem likely to be the answer your teacher wants. Until you can explain clearly what it is that you need to do you will not be able to write a program to do it. First step: describe the problem.