Hard to tell from the photo, but some personal observations:
follow the neutral/earth bus bar to the terminal to figure out which terminal is attached.
Your earth and neutral must be isolated when attached to shore power.
You are missing bushings in the knockouts for preventing abrasion. (I know it's just rough right now, just pointing it out)
The screws and fastening of your panel to the frame do not look "proper and workmanship-like" (if I was inspecting)
There's a bonding screw installed (can't isolate your earth and neutral with that)
There aren't enough bus bars to perform isolated earth/neutrals in this model of box without adding parts.
Please don't take this the wrong way, but you need to read up on electrical conventions for rvs, specifically for the americas (assuming you're in the usa). Determining which terminals are hot, earth, and neutral should be easy enough just by inspecting the box.
If you were to simply install breakers and wire things in an obvious way with how it is currently configured, there is a high likelyhood you could energize the chassis with a single faulted circuit.
This is a good book to start with:
https://www.amazon.com/gp/product/0990527913/ref=ox_sc_sfl_title_4?ie=UTF8&psc=1&smid=ATVPDKIKX0DER