You’re not going to want to hear this, but trade the car for a manual.
It can be done, but requires a lot more than just buying a manual trans from another civic. You need a new ecu, wiring harness, gauge cluster for the interior, cutting the firewall to run the clutch, interior trim pieces for the stick shift etc, and it keeps going. You’d need ecu programming done to make the new ecu work with your ignition/keys/anti-theft. If you don’t have experience with doing this type of stuff (which it sounds like you don’t), you’d be way better off swapping cars. The auto is more expensive than the manual anyway. You should be able to save yourself money by finding a manual and selling yours. The amount of expense and time to swap to a manual would be crazy.