Sette Camara was previously on Red Bull's books as part of its Junior Team back in 2016, while he spent last year in a test and development role for rival F1 team McLaren.
He will share his F1 duties this year with Red Bull's long-serving reserve driver and Nissan e.dams Formula E regular Sebastien Buemi.
"I am extremely happy to join the Red Bull family as Official Test & Reserve driver for the 2020 Formula One season alongside Sebastian," Sette Camara said.
"I’ve been watching F1 since I was five years old and I’m humbled to have been given this opportunity to work with Aston Martin Red Bull Racing and Scuderia AlphaTauri."
Originally let go by Red Bull after finishing 11th in his second season of European F3, Sette Camara has since contested three consecutive campaigns in Formula 2.
He finished 12th, sixth and fourth in those respective seasons but is not on the grid this year, having already amassed the 40 required points for an FIA superlicence.
Sette Camara has tested with Carlin in IndyCar and with Dragon in Formula E this year already, having likewise joined the latter operation as test and reserve driver.
The Brazilian, who is yet to officially firm up his race programme for the coming season, will be present in his new F1 role at the season-opening Australian Grand Prix this weekend.