Some considerations when installing a 120V single phase marine AC system. This is far from covering it all but is a start.
#1 Any AC panel on a boat should have a reverse polatiry indicator circuit. That panel does not have one. If it does not have a reverse polarity indicator then each branch circuit needs to be a double pole breaker just like the main AC breaker. Without a reverse polarity circuit each branch breaker needs to interrupt both the AC HOT/BLACK and AC NEUTRAL/WHITE. Your panel can't fit two more double pole breakers so a reverse polarity circuit would be required. This could be achieved by installing a double pole breaker, preferably an ELCI, with reverse polarity, ahead of the panel you have. it is preferably installed as close to the shore power inlet as is practical. If the wire distance, not
the as the crow flies distance, between the shore power inlet and main panel is more than 10 total wire feet this breaker needs to be there anyway.
#2 AC NEUTRAL/WHITE and AC GROUNDING/GREEN must remain isolated on-board the vessel and can only be
bonded back at the shore power supply. The only time AC NEUTRAL/WHITE and AC GROUNDING /GREEN can be bonded on the boat would be when a genset or inverter are operating as the AC SOURCE. Once these sources are shut off, that the NEUTRAL/GROUNDING bond needs to be broken.
#3 AC GROUNDING / GREEN needs to be bonded to the vessels DC ship ground bus but
NOT AC NEUTRAL/WHITE.
#4 Current safety standards require an ELCI main breaker. That panel does not have an ELCI.
#5 If plugging into shore power you will want to install a fail safe type galvanic isolator.
#6 Beore wiring any AC sytems on boats please study, and fully comprehend, the current ABYC standards as there are differnces/nuances betwenen shore and boats that are critically important.
#7 Also take some time to research
Electric Shock Drowning.
#8 If you don't understand the AC system nuances mentioned above please consider hiring a professional who can wire your boat to meet the current safety standards.. AC and boats can kill.
The diagram below is the easist way to properly install a 120V AC system on a boat. However, it assumes you have a reverse polarity circuit which would need to happen with your AC panel before you could use this diagram. You could do this by installing an ELCI with reverse polarity before the AC panel. In other words your panel does not work as a marine AC panel if following ABYC standards.. For safety reasons, any installed AC system should follow the ABYC standards.