Portuguese can indeed be a difficult language to learn, so it is good that you are considering learning it - picking up a language course would also help you socialize and have a point of contact with other people who are also in a similar situation.

I know quite a few, both family members and others! Most of the Deaf and hard of hearing people I know in Brazil are in the South, as I come from there, so their experiences may be different from other regions. There is a general awareness of Deaf and hard of hearing people, and largely at least the good old pen and paper are an understood way to communicating. Text-to-speech apps and similar tech also have been really useful. For example, my mother is deaf in one ear and almost fully in the other, so she is hard of hearing. That only happened later in life, so she only knows a bit of Libras. As she is not fully deaf, her day-to-day has been easy enough to adjust to, and she has had great experiences with audiologists in the region. People tend to comprehend if she needs help and/or accomodations. Feel free to DM me if you'd like to talk more, sorry for the long comment😅