I recommend reading this section of the “Spanish colonization of the Americas” Wikipedia article, which has plenty of sources. Obviously they weren’t saints, but, at the time, they were “the dawn of human rights” (cited in the article) and took Christian values very seriously, which is also why they converted all the population forcefully. There’s no denying that, but, as a silver lining, education and religion were almost one and the same, and they did build many universities, schools, etc.

When I visited the United States, they always tried to paint it as “they were all equally bad” when it came to colonizers in the museums I went to. However, I feel like that is because the “situation” with natives was way worse in North America than it was in South America.