Domination victory is literally one of the victoru conditions of Civ 6. You’re allowed to go full steamroll and go to war with everyone. Some of the civs are focused on going to war and expanding quickly through warfare like the Aztecs. Just don’t be surprised when you keep attacking other civs and the other players use the other diplomatic strategies to their advantage.

I’m Civ it’s also important to know how the other players perceive you and how to manipulate that perception to your advantage. Manufacture Casus Belli, poke and prod until others make the first attack and you “defend” yourself by taking their cities. You’ll be less of a warmonger.