Transport lines can be created/edited/deleted from the computer/smartphone. In total you can build as many transport lines as you wish. Each line has 2 directions.
1 - Spawner block which spawns the bus nr 7 with screens displaying direction B.Imagine you are waiting the bus at the green end stop. Spawner block spawns the bus with B screens (1). The bus drives to the stop, stops and opens its doors. At the green end stop the screens change from B to A automatically before the bus leaves. Then the bus closes doors and leaves in direction A with A screens displayed. The screens display can be switch between A and B directions also manually when driving.
To spawn a specific transport vehicle for driving use the vehicle (for example "Electric bus") item. Right click with it on the street, facing the direction you wish the bus to face. Diagonal spawning will not work. Then to assign a line to the vehicle, right click with the transport wrench near the vehicles front. It will open up a screen where you can choose the line. If you wish to display the other distination/direction then click the button "A" at the top right of the screen.
To spawn the busses automatically use the Transport spawner block. About 100 to 400 blocks before the stop/station place the spawner block on the road or on the tram tracks/rails facing the stop. Then the screen opens where you can choose the specific line what you wish to spawn. If you wish to change the line later, you can always open the screen by right clicking on the spawner block with the transport wrench.
To remove any vehicle you can use vehicle remover wrench and right click with it close to the bus. Or you can remove all the transport and traffic by pressing F3 + N twice (changes gamemode to spectator mode and back to creative mode).