Making a bullet fly and become a physics object on collision

[kind yoke]

I wanna make a bullet object which essentially has two states, the first being moving at a constant speed in a single fixed direction, and the second being acting like a physics object with collisions with the world and player. The bullet should switch from the first state to the second on collision with the world. What should I use to accomplish this? Should I have a single bullet object which is a RidigBody3D or have it turn into a rigid body on collision or something?

[nocturne ruin]

I'm don't know much about 3d and I'm not an expert in godot
But in a 2d game I made, I used apply_impulse()

You could try using apply_impulse(...) or apply_central_impulse(...)