You have 2 options for plugging in your camper at home. The simpler option is to just use a regular garage outlet and plug into that. The more complex option is to install a proper RV outlet and plug into that.
Regular Household Outlet
You’ll need an adapter for the RV end to go from your power cord down to an extension cord size.
When picking a cord, I find it best to use a 12 awg (American wire gauge– it defines the thickness of the wires in the cord + how much power it can carry) cord or larger (aka a lower the number, the larger the cord).
And then it’s about managing expectations. For the simplest answer, running A/C on a garage outlet is a losing proposition. There are ways it can be done, but it’s still fraught with being right on the balance of the amount of power available from the outlet.
Installing an RV Outlet
If you want more power, the alternative is to install a proper RV outlet for your rig. Go with a 50amp outlet for future proofing any rig upgrades or get a 30amp outlet for less cost and less power available.
You’ll need a breaker (double-pole breaker for 50amp and single-pole breaker for 30amp), wire to get to the point of installation, and an outdoor rated outlet.
Bear in mind the expected voltages for RVs: