Verifying reCAPTCHA2 in web forms

Question

I have made a form with reCAPTCHA2 validation.
I don't know how to verify the captcha. There is no proper example on google developer website. I have found following stackoverflow discussion but on every answer it is written that "the answer is not correct, or it is not contacting server" etc.
https://stackoverflow.com/questions/27902539/how-can-i-validate-google-recaptcha-v2-using-javascript-jquery

Answer 1

BroFar the answer is just a reference as it is not properly working and some people have pointed it to be incorrect.

Answer 2

ok so do you have a question as you gave us both a question and answer from stackoverflow...
https://www.sololearn.com/discuss/1316935/?ref=app

Answer 3

how about this one ( https://developers.google.com/recaptcha/intro ) ?

Answer 4

Taste in the first answer of the stackoverflow discussion, another person has mentioned that the it is not sending the request to google server for verification and only verifying on client side by JavaScript. It is okay.
How can we verify by google server ?

Answer 5

https://developers.google.com/recaptcha/docs/verify