First consideration is what is on there already,
Secondly does it need priming.
As most of my boats are ancient refurbished models, I prefer to use car paints in rattle cans on large areas as they are relatively cheap and usually have good colours available. And primers to suit.
But all my detail work I use humbrol enamel.
And if needed I will coat with polyurethane lacquer.
For woodwork I use letonquinures gold marine Varnish.(probably spelt it wrong). See picture.
Hope that is helpful for you, cheers Colin.