EPA ratings for the 4cyl Toyota Camry are usually 21mpg city/31mpg highway/25mpg combined.
Actual owners seem to report close to the combined figure.
https://www.fueleconomy.gov/mpg/MPG....ta&model=Camry
If you properly maintain your Camry (such as proper tire inflation), and you drive carefully (coast a lot and stay off of the brakes), you could probably see in the 30s, but...
Remember that the Camry is a midsized sedan with a lot of features that are standard... more convenience items and a larger size means more weight, which leads to lowered fuel economy...