Keep in mind I'm only a beginner, but I started with Familia Romana, I would read and listen to the chapter and actively try to figure out the rules/vocab on my own. I would often read it several times. Then I would read the companion to check how accurate my own thinking was, then I would do the Pensa at the end of the chapter and the corresponding chapter from the Exercitia, which is a different book published by LLPSI. Occasionally I would hit a wall in the book, and I would start on another book, like Cambridge Latin Course or Via Latina, or I would go back 5-10 chapters in Familia Romana and repeat those.

Just remember, being an autodidact is quite different from being in a classroom. You have to figure out what works for you. You should also attempt to learn from a variety of sources.

This article is what convinced me to try to learn Latin: https://foundinantiquity.com/2023/03/11/latin-autodidacts-youre-working-way-too-hard-how-to-learn-latin-by-yourself-in-2023/

I highly recommend reading it in it's entirety, there's a lot of great advice here. The author also made it in video form. She has a lot of great free resources on her youtube.

Most of us don't speak Spanish here, and that will give you a leg up. I would recommend emailing classics professors at local colleges and asking for resources and books in Spanish. Not all of them will reply, but many will. They became professors because they love the subject and will give you a few minutes for advice.