Cannot connect from WebRTC with Free switch server (SIP) - Android

Question

1. I want to establish or register or connect WebRTC to Free switch server (SIP) by using username, password and domain.

2. I want to make a call from WebRTC to Free switch server (SIP) by using extensionNumber (Ex: 1012), password (Ex: xxxxx) and domain (Ex:[email protected])

3. I want to share the screen both in Audio and Video calls (One-to-One/Conference) in Android.

4. First I should register or establish the WebRTC connection with the Free switch server (SIP).

5. I had tried two references https://www.youtube.com/watch?v=_-GPHNSug2Q and https://www.youtube.com/watch?v=pAr9E4D5lNo&list=PLFelST8t9nqgxJiD4uRN_3F1sn5rQhhw_ but I don't need Firebase to login.

6. Also I need only to connect, call and share screen from WebRTC to Free switch server (SIP).