Jewish heritage

So, I’m a Brazilian 21yo man and last Sunday we had Father’s Day, as I’ve moved cities to go to college I went back to my home town and we had quite a nice weekend. I’m really interested in discovering my ancestors and l had already talked with my mother and could track down my family down to before 1700 and I’m kind of related to a past of Portuguese aristocratic and slave owner family, Pinheiro Machado, which really put me off. Otherwise, talking to my father he told me his grandparents came from Portugal and Italy at late 1800, but our last name, Moreira, is quite generic in Brasil. Tracking down this family name I came across a lot of things about the Portuguese Real State forcing a lot of Jews to convert into catholics to keep their houses and lands in Portugal, becoming ‘new-christians’ as opposed to the real families and traditional families of the realm, the ‘old-christians’. In this forced conversion people changed their Jewish last names to names related to nature (Moreira stands to Amoreira which means strawberry trees, Ribeiro is linked to rivers, Oliveira is linked to olive trees…) as a lot of ‘new-christians’ kept their Jewish practices at home, Inquisition went after them and some of them had to escape to America. I’m not really sure if the dates match, as immigration to Brazil happened for a lot of other reasons throughout the 19th century.

I’m a bit confused with where to study about this, as my family was not actually rich or important to have it all recorded and written. Do you guys have any recommendations?