Hello Anthony, and welcome to the forum!
The Block Section of track is usually used to isolate a section of track to operate accessories. The accessory terminals on your transformer are used to power accessories since the voltage is steady and not variable, which would be needed to operate a train with.
Without a form of command control, it is very difficult to operate 2 trains on one track manually. The best that can be done is to use block sections with relays to stop and start trains in the blocks. The relays would control the trains, and they would run on their own with no operator assistance. Here is a nice tutorial on wiring up a layout that way.
Running 2 trains simultaneously would be much easier with 2 separate loops. In this case, you could use the fixed voltage accessory terminal of your transformer to run one of the trains at a fixed speed, and the throttle would operate the second train. To have independent control of both trains would need either 2 transformers, or a larger transformer with 2 or more throttles, such as an old KW or an old or new ZW transformer.

Larry