**"Estou fechado com Bolsonaro e não abro."** **You're right, it's not to be taken literally.** "Estou fechado" is a slang phrase for "I totally agree with", "I'm committed to", or "I'm wholeheartedly dedicated to". It's often followed by "e não abro", also a slang phrase meaning "and I won't change my mind", "I won't rethink, "won't reassess". "ok, estamos fechados" = "ok, agreed." Whoever says such a sentence these days, should have his mental status evaluated by a psychiatrist. (personal opinion)