How can i open the trapdoor in the house of the Shaman? Where can i find the utilities so finish be a samurai?

Talk to the Shaman and he should open the trap door.

To finish the Samurai quest you have to be able to get to Surugen Castle. There is an area on the east side of the castle that you can only reach by swimming through part of the moat. You'll be able to find the samurai baton there.

Wyv

if this is the toad shamon you have to say "ukabu" to him.