Twilio Settings
Go to settings -> System Settings
Head to this url https://console.twilio.com/
Create A twilio account and then follow these steps
Copy Account SID and Auth Token and paste it in :- Admin panel -> Settings -> System Settings
To Get Number you can buy the available number or you can get trial number
Or you can get trial number from here
Copy the number and paste it in System Settings and save the form
Note :- In Trial accounts, numbers will not be verified automatically, if you wants to send the otp via twilio you have to verify your number manually in twilio