ONT wired to fuse box?

[Nimnard]

We have a backup generator (lithium battery) that we use during power outages. We can keep our router powered up but the ONT doesn't have a conventional cord to plug into an outlet. It appears to be connected to the same wire going to the fuse box (see photos).

Is this something we'd have to have a Verizon technician change and would it be a major hassle? It would be nice to be able to have the ONT provide the FIOS interent plugged into our generator during a power outage.

[Edg1]

That wire is the ground wire not the power wire. The thicker beige wire which is the second one from the left is the power wire.

Trace out that wire to see where is goes and there will be a battery backup and/or power supply unit which plug into a standard receptacle.