If you are a wizard, you don't have the spell on your spell list. You could gain it through the Samsaran racial option (from the bard spell list). Or you might find it on a staff, but the spell only allows for attack commands.
Share spells does not work like that, you should reread it.
You could craft the mount instead of using the spell through the craft construct feat. Maybe for Clockwork steedbut it would be a horse and would accept commands just like one.
If you are the GM, this is not worth the time or effort to figure out. Just re fluff an intelligent minion or add an animated chair that follows commands for the person on it. I am not sure what you want the move action for but it will not matter much if the combat is 1 enemy vs 4+ PCs