Defender Gabriel Magalhaes headed Brazil ahead from Neymar's corner shortly after half-time, before Real Madrid forward Vinicius Jr had a goal disallowed for offside.
Bello made them pay when he netted spectacularly with five minutes to go.
Brazil fall to second in South American qualifying after three games, behind Argentina who have a 100% record.
Argentina earned their third win from three games in Conmebol qualifying with a 1-0 victory over Paraguay thanks to a brilliant goal from former Manchester City defender Nicolas Otamendi.
The 35-year-old scored his fifth goal in 106 international appearances just three minutes into the match in Buenos Aires, via an acrobatic back-post volley from a corner.
Lionel Messi, who has been struggling with a muscle problem in recent weeks, came on as a 53rd-minute substitute for the 2022 World Cup winners and struck the post with a free-kick late on.
Uruguay, who host Brazil in Montevideo in their next fixture on 17 October, earned a 2-2 draw away to Colombia thanks to a late Darwin Nunez penalty.
The Uruguayans, now managed by former Leeds boss Marcelo Bielsa, trailed to James Rodriguez's 35th-minute strike but equalised through Mathias Olivera shortly after the interval.
Mateus Uribe restored the Colombian lead, but in the 87th minute their goalkeeper Camilo Vargas was sent off for fouling Maxi Araujo in the box, with Liverpool striker Nunez netting the penalty to earn a point.
Elsewhere, Chile beat Peru 2-0 while Ecuador won 2-1 in Bolivia.
All 10 teams in the Conmebol confederation play each other twice in qualifying, with the top six sides in the table reaching the 2026 World Cup in Canada, USA and Mexico. The seventh-place finisher goes into an inter-confederation play-off.
