New runner - debating using Runna

Hello!

I am newly getting into jogging/running. My goal is to be able to run 5km straight (either on treadmill or outdoors) by April/May. I recently came across Runna - what would be the benefit for me to use Runna and how does it integrate with the Apple Watch?

For context, I'm currently on week 2 (3 days per week) of a plan I found online that is a run/walk interval run schedule that gradually increases the run time/distance.

Thanks!