Whatever command works in the shell, you can just put it into a textfile that starts with
make that executable with
chmod +x /path/to/file
and run it. Your command uses relative paths, so either you'll want to change it to use absolute paths or put your script into the same directory as the awk scripts and run it there.
If you want the command to run twenty times you could either
a) put the command 20 times into your script (very unelegant, but maybe a good place to start for a newbie)
b) look into the syntax of loops in shell scripts.
As far as outputting to excel format: No simple way that I am aware of, but depending on the output of your command you could probably output as csv, which can then be imported to excel. Maybe your command is already doing that (impossible for me to tell as I don't know ns and can't see your awk scripts), so if you want to pipe the result of your command to a text file you can use a so-called redirection operator (> or >>):
command > outputfile.csv
Depending on the redirection operator you will
- > : create a new output file, overwriting an existing one if any
- >> : append to an existing output file if it already exists or create it otherwise
One last side note: The first line of the script I mentioned above gives you a basic shell, which you can be reasonably sure will be available on any linux distro out there. For more complex scripts it's sometimes useful to use bash instead:
I use that all the time and find it more convenient to use than plain sh, but it is less portable so some people will recommend against it.