Spawn AI in groups

Hii, I was following. Some rts tutorial, but I have a problem, I want to create a spawn AI in groups/team.
I explain, the idea is this: click a banner = spawn 10 npc group; click another banner spawn another group of 10 different npc. I want that this group move togheter not like in rts tutorial where you select one unit at time.

how I do this? You know some tutorial? Thank you.