This is just a note on which other tutorials worked for me! after spending way too long finding the info.
The main config steps in Grafana are getting the email working and setting up domain names, they are in the etc/grafana/grafana.ini file:
domain: yourdomain.com
root_url = http://localhost:3000/
[smtp]
enabled = true
host = localhost:25
skip_verify = true
from_address = noreply@yourdomain.com
from_name = yourdomain.com
ehlo_identity = yourdomain.com
This is a very verbose and well thought out tutorial on the bulk of the steps to get nginx working.
https://tom.busby.ninja/letsencrypt-nginx-reverse-proxy-no-downtime/