English is very difficult to learn because there is no consistency in its sounds, grammar, and pronunciation. Even the same word has different meanings depending on its pronunciation, and can have different pronunciations depending on its meaning! An exaple would be the word "lead." It sounds like "leed" (and rhymes with "bead") if used as a verb, but sounds like "head" if it describes the metal. And why "lead," as in the metal, rhymes with "head," "bed," and "led" but "lead" (the verb) rhymes with "reed," "weed," and "bead" is crazy and takes a while to learn even for native speakers.
I lnow you're a Portuguese speaker, but if you understand Spanish at all, check out "Superholly" on YouTube and Instagram. She is bilingual and fluent in both English and Chicano Spanish, and has no trace of an accent in either (she is a native speaker of both). She has a video, in Spanish, that describes something like "11 mistakes Spanish speakers make when speaking english" that touches on pronunciation it might be helpful!