trying to trigger a flow after another flow ends following instructions in https://docs.prefect.io/core/idioms/flow-to-flow.html when registering the flows A, B, C and D, in the example, I assume we register them without a schedule, is this correct ? I also do not see the in the python example code the

flow.register(project_name='example')

we do need to run

flow.register

, right ?

That is right you register them without schedules (or you can), but then you would schedule the “main” flow and that would run all of the subflows. Yes you do need to register these, but that can also be done from the command line with

prefect register …