My girlfriend will meet with me in Cancun , Mexico due to a complete change of plans . I am not going to Brazil due to the potential for infection or lockdown . I am a US citizen. We agreed to meet in Mexico since Brazilians are banned from visiting the US under Trump and Biden for the time being . Question - how about just traveling from Brazil to the US city of Miami, Florida for a 3 hour layover ? She would be flying from São Paulo to Miami, have a layover for 3 years without leaving the airport obviously , and then fly from Miami, Florida to Cancun, Mexico ? Can Brazilians do that , just through transit, pass through Miami or another city on the way to another country ?