you add the ups to ups.conf, mine looks like this:
[ups]
driver = snmp-ups
mibs = cyberpower
port = 192.168.0.250
community = public
snmp_version = v1
pollfreq = 15
desc = "RMCARD205"
Obviously not the same model but that was it for that file.
Now the NUT server @ localhost will report the data just like it was plugged in to the server, so you need to monitor it.
In the upsmon.conf file, you add
MONITOR ups@localhost 1 homeassistant homeassistant master
homeassistant is both the username and password I am using for authentication in NUT, and it needs to be here as well.
I think at that point, restarting the NUT services is all that is required to get it to show up in HA, assuming you already have the integration connected to the NUT server