In the same way as for the other Farming Simulators. If you are PS4 / PS5 / XBOX ONE / XBOX SERIES S / X players, you just have to go to the game's “mods” menu. The mods install themselves.
For PC gamers who download mods, just place the downloaded ZIP file in the directory C: \ Users \ YOUR USERNAME \ Documents \ My Games \ FarmingSimulator2022 \ mods.
Then you have to start your game and activate the mods by checking them.