Wait! I can not teach you anything as same angler.
What kind fish you want?
Do you know what kind of fish that we can fish in Japan?
Solo or group? family? w/wife, kids?
What kind boat you are thinking?
乗合船 oiriai sen、貸切船 kashikiri sen? or レンタル rent?
rowing boat? 手漕ぎボート
sea kayak? シーカヤック (canoe? カヌー)
raft? 筏(いかだ), floating fishing spot in bay.
Where did you live in Japan? Tokyo?
Do you fishing in Singapore? If so, what kind of fish?
Anyway, small remote island is better.
民宿 for anglers is called "釣(り)宿 tsuri" or "船宿/舟宿 funa yado" generally.
But you can do boat fishing even if you do not book a such yado.
Alsol 2馬力(2PS engine/motor power) max and 3.3m size mini boats is not required boat license.
However, as the number of accidents increases, the Japan Coast Guard is alert.
This is met their patrol and check "臨検 rinken" on the sea. https://youtu.be/VvrTtRHm_R4