Here is a short game play video of Halo Wars 2. It's a Real Time Strategy Game. Basically in these types of games you play the role of a General/Military Commander etc... it's a overlord type view as you are commanding ALL of your forces. Infantry, Air, Naval etc.. so it can get a bit hectic and takes time to master. You have to basically micromanage all of your forces, tell them who/where to attack, or if you want them to defend a certain area, call in air strikes all that stuff. It can get hard on large maps where you might have to separate your forces to attack from different directions, or to take out multiple targets at once. Anyway, they are very fun imo, but very time consuming. You have to build a base, gather resources, make base defenses etc... Can spend hours on 1 mission easily.
https://www.youtube.com/watch?v=yHaFqic7hP4
https://www.youtube.com/watch?v=yHaFqic7hP4