I guess that you want to have a feature on your web page that lets a page visitor to call you by clicking a button e.g "Call us" instead of asking them to dial your number on their phone. If so, here are the instructions.
1. Provide the button e.g. "Call us", when a visitor clicks the button, display an input asking him to enter his phone number. Or next to the "Call us" button is an input field "Enter your phone number"
2. After the visitor enters his phone number and clicks the "Call us" button, send the phone number to your backend and make a ring-out call from your backend.
var params = {
'from' : { 'phoneNumber': "Your-Phone-Number" },
'to' : {'phoneNumber': "Your-Visitor-Phone-Number"},
'playPrompt' : false
}
When you make that /ring-out call, any phone associated with the "from" phoneNumber will ring. So on the sandbox environment, if you login the RC app for sandbox, the phone on the RC app will ring. On the production environment, your RC app (desktop and mobile) will ring.
You can also test with your PSTN number by setting the "from" phoneNumber to your mobile number.