Twitch Event-Sub verifying callback

In twitch docs, wrote what ‘Twitch won’t send you events until it verifies the callback.’, how i can verify it?
page on which it wrote Manage Subscriptions | Twitch Developers

EventSub is a WebHook “Style” notification platform

So when you call “Create subscription” - Reference | Twitch Developers

Twitch will then make a HTTPS POST request to your transportcallback defined in your Payload.

And when Twitch makes that HTTPS POST call to your callback you verify the payload is from Twitch and expected, then echo back the challenge from the POST body. Then if this step is completed OK then Twitch will treate the subscription callback as verified

The callback needs to be protected by a “real” SSL Certificate. And be a URL/WebServer that is publically accessable.

Okey, thanks you