Is it like in Spanish where the pronouns aren't necessary? Or are they used like in English? Because in Spanish it just adds emphasis
According to what I've read in the comments for Portuguese on Duolingo so far, it looks like you mostly can, but it's not good to do it for Ele Ela ( "he" "she") because they share the same verb conjugations as você ("you") so you might confuse someone by leaving them out.
Correction: Ele & Ela. Don't know why it didn't show up that way & won't let me fix it.
I think you could omit them when the subject is eu, nós e eles/elas, but unless you use tu instead of você, I wouldn't recommend omitting if the subject is você. With ele/ela depends on the context!
but also we do in Spanish, the conjugations for "usted" or "él/ella" (you and (s)he) are the same, and we actually omit them, but Idk why Duo doesn't allow me to omite them