For anyone who is new to Orthodox Christianity or looking to learn more about the faith, the Greek Orthodox Archdiocese of America and the Orthodox Church in America provide extensive information on their websites:
https://www.goarch.org/introduction
Spanish / Español: https://ocamexico.org/centro_de_catequesis.html
There is a wealth of information about Orthodoxy online, but these sources will provide both a firm foundation for getting started as well as referrals for further learning.
Inquirers are strongly encouraged to "taste and see" Orthodoxy by visiting a parish for services and events, speaking with parishioners, and experiencing the faith firsthand.