A flow can be launched from a Process Builder to make complex automations. The only limitation is that the flow must be an autolaunched flow. Flows will be covered in depth in the next chapter, that is, Chapter 14, Lightning Flows.
To configure a flow action, select an autolaunched flow and set up any relevant flow variables by picking from the current and related records:
Flow action
Remember, only active flows can be selected for this configuration.