wget 'https://raw.githubusercontent.com/kulga/flarummanagement/master/flarum_management' -O flarum_management
chmod u+x flarum_management
./flarum_management -if 159.203.11.26
cd /
cd var
cd www
cd flarum
composer require flagrow/bazaar
Starting from right here, it does not install to /var/www/flarum, it installs to /var/www/flarum/*sitename* in your case likely /var/www/flarum/159.203.11.26. This would be the flarum root directory.
I may make this more clear in the script
I have tested this script with the command luceos gave in the flarum root directory and it does work
You can use the ls command to see what's in the directory you touch.
I would suggest going through something like this to familiarize yourself with the command line.