Getting married to a Portuguese then bridging the gap. Need clarity on pathway.

I'm a US national currently living in the States getting married to a Portuguese national who resides in Portugal this year. We will marry in Portugal and everything is set for that. I plan on moving to Portugal with the intent on using Article 15 as a means to stay legally until I become eligible for citizenship after 3 years of marriage. My question is, do I enter Portugal as a tourist (visa-free) or is there a specific visa I should be applying for given my goal? =
I researched about the application process for Article 15 and it states an eligible applicant may apply within 30 days after three months have elapsed since entry into national territory.

However...if I enter as a tourist, I am required to have a return ticket within 90 days...which would make me delinquent while applying for Article 15 right?

I keep seeing info about using the Family Reunification visa but from my understanding, that doesn't pertain to when reuniting with a Portuguese citizen.

I'm just so confused about in which manner to travel there prior to applying for Article 15. Any help would be very much appreciated!