1. Head to https://firebase.google.com/ and click on Go To Console
2. On the console page click on Add Project
3. Create a project by filling out your Project Name (Wesbite Name), Select your location and agree to the terms
4. Once your project is ready, click on Continue
5. One next page under Project Overview select Authentication
6. On the Authentication Page switch to Sign-in Method tab and click on Phone to edit that, Enable phone and then save the changes
7. Scroll down on the same page to see Authorized Domain section and click on Add Domain
8. Fill out your domain and click on Add button. (If your website is on subdomain then use your subdomain)
9. Scroll back to the top and click on Web Setup button, make a note of these API values from here and use these values in digits gateway settings.