The best way to assess yourself is to go out for a jog. Try covering 5 km and check the timing.
An app like Nike Run or any other running app can help you check the distance and time.
If you can cover 5 km in 45 mins by brisk walking, that’s good timing.
If you are jogging, you could take around 35 mins to complete 5 km. That’s also good timing.
This is just one way of assessing your fitness. If you’re cycling, you should be able to cover 22 kms in an hour.