For most signalling you want the path signals. They come in 2 flavours: both kinds only do the path in one direction, one kind is non-blocking to trains running the opposite way, the other kind is blocking, one way only.
This combo lets you set up an upline and downline with a terminal station: you have one way only signals on the line, and non-blocking signals on the station entrances pointing into the station, and a crossing between. Trains will get to the end of the upline, and wait to get a path to the end of the station. Then they'll turn around and wait to get a path to the downline.
