is there a way to add commands to buildings\units?

If you mean adding buttons to units, yes. There is a program called Firegraft that lets you edit the button sets of units and buildings. However, it only works on Starcraft versions 1.14, 1.15, and 1.15.1. So your mod will not be able to be run on the latest version if you use it. Firegraft also has the capability to edit certain aspects of starcraft controlled by the executable, such as the capacity of carriers.

Also, be aware that the computer AI does not use buttons. Instead, it uses unit/building requirements directly.

it depends on what u mean, if you mean add something like move, attack, or patrol, stuff like that to a building, then yes, use firegraft to edit buttonsets

if you are trying to create a new KIND of command, like patrolling between three points, then no...

[quote modmaster50]Starcraft versions 1.14, 1.15, and 1.15.1.[/quote]
urg, anyway to downgrade "temporary"?

urg, anyway to downgrade "temporary"?[/quote]
SCD3 (Starcraft Downgrader 3) can downgrade your starcraft version. I recommend using 1.15.1, as it is the latest version that Firegraft works on. If you make it on 1.14, my computer will probably hate your mod (by giving me an error screen: Cannot find file called "unit\" !!!)

thanks