Invert collision detection for boats

I’m pretty new to Unity so forgive me if this is obvious somehow.

I have a tilemap with a TilemapCollider2D, and the map is a grass island in the middle of water. The water tiles are collidable because I don’t want the player to walk in water (this makes sense)

What I’d like to implement now is a boat that the player can enter. The boat should be able to move on water but not go onto land, so basically the reverse of walking.

Is there a way I can “reverse” the collisions when the user switches to/from the boat?

Try a layer mask, basically it only acts as a collision on what you select or don’t select, I forgot exactly which it is:

public LayerMask mask;

I think from there it should show up in the inspector and then add that to your boat script, just make sure your land layer and boat layer are properly defined.