https://www.gamespot.com/articles/civilization-6s-first-expansion-rise-and-fall-reve/1100-6455221/

Publisher 2K has revealed the first expansion for Civilization VI, called Rise and Fall. The expansion adds eight civilizations and nine new leaders, along with a variety of new systems to further bolster the turn-based strategy game.

In addition to the new civilizations, Rise and Fall adds eight new world wonders as well as new units, districts, buildings, and improvements. It also expands the Government and Diplomacy systems, allowing you to form new types of partnerships with other civs that can provide new bonuses. It also adds Great Ages and Governors, which are characters that can be hired to further customize a city.