Here is a previous thread on that topic...
If it is not pre wired see my post about installing an AC hard wired to an exterior plug for a 30 amp trailer or to protect the generator on a split panel.
On shore power you can run 3 ACs, but 2 ACs on one side of the panel is going to cause issues with the generator if it is not run through a power management system. If you do not have a 3rd AC from the factory, you probably do not have a power management system / PCS.
If you are going to TRY and run 3 ACs on the generator w/o a PCS you'll need to buy a high efficiency unit, add hard start capacitors and run your Fridge & WH on propane to MAYBE get 2 ACs to run on one side of the panel that is protected by a 30 amp breaker on the generator.
Otherwise you can be the power management system manually switching between the garage & bedroom AC as needed.