The Brazilian government provides a well-organized, multilingual webpage (available in English, Spanish, and Portuguese) with comprehensive information about visas for foreign visitors:
https://www.gov.br/mre/pt-br/assuntos/portal-consular/vistos/informacoes...
There, you will find useful information on topics such as:
- Do you need a visa?
- Where to apply for a visa?
- Visit Visa
- Mercosur citizens
- Visa for minors
- Invitation letter for foreigners

Additional information for US passport holders:
https://www.gov.br/mre/pt-br/consulado-miami/information-about-visas-in-...
Brazil will resume requiring visas from citizens of Australia, Canada, and the United States.
The measure, approved by the Brazilian government, will take effect on Thursday, May 10, 2025.
The visa application must be completed online, with a fee of US$ 80.90, and the stay may not exceed 90 days.

For information on obtaining a conference supporting document for your visa application, please contact the FGV-EMAp staff:
Thais da Silva <thais.mancilio@fgv.br>  and  Roseni de Souza <roseni.souza@fgv.br>
(include the following information: full name, institution, passport number, nationality, and a scanned copy of your passport).