programming npcs in game

How would you make it so both players can click on a thumbnail to add a particular vehicle or soldier and tell them in a certain sequence by clicking on thumbnails what enemies to attack one after the other?I want them to be ableto click on start when theyre finished and it will start the battle.I would like it to use navmeshes as well.

You are asking for a game!
There’s no one way of doing it!
In my thread player- object interaction, I’m studying ways of allowing easy interaction with objects in the game. That will include setting npc modes, creating in game programs, or just open a door!
I advise you to follow it, specially Monster’s interventions!

Sounds like a command pipeline. This requires some Python knowledge.

What you can do is to add the commands of clicked thumbnails into a command pipeline (list). The NPC can take the first command from the command pipeline. The NPC acts according to this command. When done it takes the next command from list. When the list is empty it can perform a default action (e.g staying around).

The most logic processes one command only. The above solution add the command pipeline to feed the logic as advised by torakunsama. If well designed you can assign a command pipeline to any logic.

Be aware to manage the pipeline you need a pipeline manager which performs the interface to the user (menus/clickable thumnails etc.).

I was thinking the property script you gave me before could help with this if modified to work with left and right mouse buttons.But of coarse it would be good if it worked with instanced objects.
What is a pipeline manager?Could it be done in blender?