Newbie question

I am trying to join a league that is open to Public not Private which would require an invite.. I simply do not know how to join.. which "Button to press on the app.. I don't see anything

You actually have to create your team first (fill out your draft list and so forth.) Joining a league is the final step.

https://365.strat-o-matic.com/member/startnewteam

Thank you!.. Got it!

You're welcome. Have fun!