I'm a bit confused on what "problem/issue" you are encountering. The title you chose and the information that you shared makes it sound like your trying to treat the symptoms rather than the disease (to borrow a medical analogy). In other words, it sounds like you want to find a way to kill an orphaned process (the symptom) rather than fixing the script that is orphaning the process (the disease).

First, you should probably modify your code so that it first checks to see if an instance of Word is running. If there is one running, use it. If not, start one.

Second, your script should include error trapping to ensure that your code does not leave an orphaned process.

If my suspicions about what you're encountering are correct, doing these things might eliminate your "need" to "end a process in windows".

(By the way, if a user is actively using Word on the remote system, ending the Word process at the start of the Perl script could create more problems for you.)