You need a thruhull to get the
water, the hose to the pump (possibly a strainer in between), and hose to the spigot (don't use your standard fresh
water one).
We use a Fynspray spigot with a foot pump. I have a three way valvle installed so that I can also use the spigot/pump as our
emergency fresh water supply. There is another valve before our pressure system pump so that we can close that entire fresh water line off so not to get air in the pressure pump nor
salt water contamination.