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 (Website Name), check your country and agree to the terms and click on Create Project
4. Once your project is ready, click on Continue
5. On 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. Once your domain is added, head back to Project Overview and click on Web icon.
10. Put in your website name in App Nickname and click on Register App
11. Once the app is registered click on Continue to Console
12. Once on console, click on your app list
13. Open app settings by clicking on the gear icon
14. Scroll down to Firebase SDK Snippet on the same page and select Config
15. Copy this script detail and paste it in digits settings.