Ceres naturally has a gravity of 0.029g (2,9% of the gravity force on Earth), but in the universe of The Expanse it has been artificially spun up to 0.3g of centrifugal force (so the "gravity" points in the opposite direction, not towards the center of the planet). There is a population of around 6 million in Ceres Station which consists of tens of thousands of kilometers of tunnels bored deep into Ceres. Ceres Station is the most important spaceport in the Belt, 800 to 1'000 ships are docked on Ceres every day, so along with the 6 million permanent residents there are an extra one million transiting through at any given time. Ceres Station was initially governed by the United Nations, but during season 1 of the show Outer Planets Alliance (OPA, a fractured sociopolitical movement trying to unite the Belt) takes control.
The life on Ceres is depicted in season 1 and season 6 of The Expanse. Here you can view some of the best shots from locations on Ceres Station (part of them downscaled from 4K UHD screens for better image quality) as well as some concept art for Ceres:
Mid-town Ceres Station:
Ceres Station docks on the surface of Ceres:
Administrative Plaza of Ceres:
Concept art for The Medina level on Ceres by North Front Studio:
