Manual install Rocket.Chat on Ubuntu not working

I have installed on ubuntu 18.04 and follow the steps

I install mongod version 5.0.7, nodejs version 14.19.1 but when I run nodejs main.js it says Must pass options.rootUrl or set ROOT_URL in the server environment even though I have set ROOT_URL as my server ip address. Another problem is mongod.service with active failed (Result: exit-code) status can’t start again
Process: 1165 ExecStart=/usr/bin/mongod --config /etc/mongod.conf
rocketchat.service also got Active: failed (Result: exit-code)
Process: 1365 ExecStart=/usr/bin/node /opt/Rocket.Chat/main.js (code=exited, status=1/FAILURE) after server reboot