How to implement mission-based game

I’m still wrapping my head around the Unreal Engine API. I’m not 100% confident in my understanding of GameMode, GameState.

I want to create a game where at the menu screen you have a list of Missions to complete, and depending on which mission you select is what the objective will be. I’m pretty sure all the missions will have the same level, although it will be in different states (different Actors spawned on the level).

Are there API classes to help implement this (ie: each Mission is a GameMode…)? Or should I create something myself?

Thanks