Hello!
The attached archive contains the code of a mini SIP phone without a video call (the same as here
https://flashphoner.com/embedding-a-browser-based-sip-phone-to-a-web-page-2/ option 1). Specify your parameters (marked in the JS file with comments), place them on your Web server and try testing.
WCS is not a SIP server, therefore, to use SIP telephony functions together with WCS, you need a separate third-party SIP server: for example, Asterisk or others. Testing requires a working SIP account
Valid SSL certificates are required for WCS to work correctly.
Please tell us more about your problem so that you can find a suitable solution.