You can automatically add your prospects into your workflow.
For that, you need to select the option Enroll prospect automatically in the Enrollment strategy.
Then select when exactly you want the prospects to be added to this flow. Select one or more triggers from the list.
Triggers are specific events, which trigger the enrollment of the prospects. In other words, once the selected event happens, the system tracks it and starts the workflow for this prospect.
You can narrow the audience of this workflow by adding filters.
Don't forget to click the Appy button after you set up the enrolment strategy.