Codes P0137, P0446, and P2270?

Hi there,
The p0137 and P2270 are related and point toward the oxygen sensor itself. There is a small change it could be wiring problem but if the wires look good and not damaged then I would replace the Oxygen sensor. Your car has two oxygen sensors. This one is pointing to the sensor after the catalytic converter or the one farthest away from the engine.
P0446 is saying a leak has been detected within the fuel vapor management system. Most likely this is a leaking vent valve but could be a leaking purge valve also. If there is a small leak somewhere else could send this code also.
I would look at replacing that oxygen sensor and the canister Vent valve.
I show the downstream Oxygen sensor is about $82 from AutoZone and the vent valve about $40 from AutoZone also.