To add phone number from web follow these instructions 1. Tap on "More" and choose "Settings and Privacy" 2. Tap on "Your Account" and click on "Account information" Choose "Phone" from the menu 3. Tap on "Add Phone Number" verify your password and click on "Continue" 4. A verification code will be sent to your phone number enter that code to activate phone number 5. And You will see your phone is activate