Pillager outposts can be generated in the plains, desert, savannah, taiga and tundra biomes.
Go to explore any biome to find a pillager outpost. A good tip is to keep an eye out for villages as well.
Because it is common for a pillager outpost to generate close to a village. Eventually you will find a pillager outpost. Pillagers outpost can spawn naturally in the game and it is surrounded by passive mobs called pillagers with collections of crossbows. The pillager outpost will have pillagers around it unless you are in peace full mode.
