The Brazilian, whose older brother Pietro Fittipaldi is reserve driver for the Haas Formula 1 team, broke the news on social media on Saturday.
Fittipaldi has been talking to Red Bull motorsport advisor Helmut Marko for some time, having been spotted having a meeting with the Austrian at the Dutch Grand Prix back in September.
Fittipaldi made his F2 debut in 2021 with Charouz, running three race weekends for the team before signing up for a full programme this year.
He logged three second places in the feature races at Imola, the Red Bull Ring and the Hungaroring respectively, and also had three third places. He lies sixth in the championship with just the Abu Dhabi finale to come.
Fittipaldi said: "It is a great honour and a very important step in my career to join the Red Bull family, who are the reigning F1 champions.
"I am very grateful for this opportunity and I would like to thank Red Bull, Dr Helmut Marko and Christian Horner for their trust in me."
Asked by Motorsport.com about what appealed about Fittipaldi, Marko made it clear that the 21-year-old had overachieved at Charouz.
"That he performed in a midfield team, I would say," he said. "He was always there on the top. I think he had his ups and downs. And now he knows there's a chance. He will be with Carlin, which is a top team. And he's a character."
Asked what the aim was for 2023 he said: "We'll look at how he's performing. Like always, with results."
Marko confirmed that not all of Red Bull's 2022 F2 drivers will remain in the programme next year.
"We will make an announcement pretty soon about who is leaving and who are the new guys."
Meanwhile, Marko stressed that Liam Lawson will benefit from his planned move to Japan for 2023.
"He will do Super Formula. It's a difficult place to be. The Japanese drivers know every centimetre, they know all the tracks, it's not easy."
He also confirmed that Norwegian F2 racer Dennis Hauger will be elevated to an F1 reserve role next year, alongside Lawson, who won't always be available due to race weekend clashes.
"We have several reserve drivers. Another one will be Hauger, that's what's decided so far. And we will see the beginning of the season how it's going. There will be some clashes, but out of our youngsters there will be two or three."
