First, clone the repository using git (recommended):
git clone https://github.com/Ramhm/zabbix-total-bw.git
or download the script manually using this command:
curl "https://github.com/Ramhm/zabbix-total-bw/master/zb_total_bw.sh" -o zb_total_bw.sh
Then give the execution permission to the script and run it:
$chmod +x zb_total_bw.sh
$./zb_total_bw.sh