Hi Ana Rosa,
Your school work for OT would need to be reviewed by the national organization called NBCOT in the US. Below is the link you will need to visit for the appropriate process and details.
Separately, I wondered if you could share your experience from when you worked as an OT in Brazil? I am interested in possibly doing the reverse and going from the US and working in Brazil. Does a therapist need to be fluent in Portuguese? Also, what are the work site options? What is the process to become approved to work there? Thanks for any details,