This will probably answer some of your questions:

Will these spawn in vanilla map?
Nope, they dont. I havent figure out how to do it yet.

Do i have to spawn those in?
Yes, unfortunately. That's the only way

How do I download the mod and use it?
Download by subscribing to the mod. After that, go to your game and type in @vehicle [id]

Where do i post bug or give ideas?
I have create a discussion for you guys to post your idea and the bugs you found.

Can the other vehicles shoot?
Only the tanks shoots, the others dont. I dont plan to add the turret system for APC and HUMVEE because the already reached the maximum amount of seats I want it to have

Why can I access the seats of f11 and f12 of APC?
That's because f11 and f12 is occupied by Steam, i believe. f12 is the screenshot for steam but i am not sure of f11 though

How to spawn vehicle?
@vehicle id. eg. @vehicle 40002

Will you make a map?
Yes, I will, in the future but it might take very long as a map is takes a long of time to make. Including me modelling new buildings and stuff to fit in the theme