Fankly, I think you should start with doing the tutorials, as these questions are quite simple and if you had done a few of the tutorials I am sure you can figure it out yourself.
That said here are some pointers, but still - do the tutorials.
You should read up on input
At the most basic of this you only need to set the position of your game object at your mouse. Now this would make a very jerky movement so this is probably not 100% what you want.
function on_input(self, action_id, action)
if action_id == hash("touch") then
gui.set_position(gui.get_node("player"), vmath.vector3(action.x, 0, 0))
end
end
This could probably be sovlved easily with paranting