Webhooks API - Much needed information

The Webhooks V2 REST API is now public ( earlier it was in BETA version ) . I need to know few information regarding the creation of webhook and the sending of 200 OK Status . Is there any limit on the endpoint with which we are gonna create a webhook ? After creatinga webhook , where do we need to send a status which says 200 OK ( Is there any specific param/attribute with which we need to send ? )