All of these items need to have their own breakers although you might be able to get away with the CB Radio
and the stereo on the same circuit provided they do not exceed 5 amps....which is not much current
for a 12 volt load.
Loads that relate to safety
such as your VHF
lights and even your cabin
lights should each have their own dedicated breaker. Its also a lot more convenient wiring
your different loads this way when it is necessary to work on then
My gut feeling is you need to buy or make a circuit breaker panel with a number of breakers so your boat is wired correctly and safely.