How to edit contacts in google contact based on c#?

Question

Google

Ideally, the program should correct the google contacts data that is synchronized with the phone, but the problem is that I don’t even know which side to approach.
Desired result:
1) We get the input data.
2) Edit the data of these contacts.
3) Timer for repetition.
How can this be implemented? I guess that the dog is buried in the google api, but at least a couple of examples would look for understanding ...