Entrance and exit: follow the steps of facility construction. Set the entrance first, close to the boarding place. Set the exit again, near where you get off. Connect the entrance of the main road with a road with its own fence. Then use ordinary roads to connect the exit to the main road.
Fast track: First, open a fast track exit near the end of the facility entrance channel, and then open a fast track entrance at the end of the entrance channel to connect with it.
The entrance and exit are directional and can be adjusted during construction.