you have a raycast which rotates toward the mouse with the help of look_at() then you check if input gets oressed rhen you check if the ray collides you grab the point of collision the you do a simple radius calculation and set velociry to the tangent or something like that(might have ti di some research for the math because i might be waffling here)
but ive defintely seen some tutorials for that which go more in depth than me