https://4chanint.miraheze.org/wiki/Portuguese
Look up some grammar textbooks, search results will give you titles. Check if they are available for download on Anna's Archive, or buy one from a local bookstore.
That wiki page will have a bunch of resources for comprehensible input too.
Good luck, I started learning Spanish myself. I would offer some advice if I weren't also a beginner like you. Ganbarimashou! (´人｀)