Implement an authentication module

Hi

I want to implement an authentication module for my application.
I want that if the user opens the application for the first time on his phone, he authenticates by entering his username, phone number, country, and then validates. An SMS message will be sent to him with a confirmation code on the telephone number he provided. It must enter this confirmation code into the application to complete the user account creation process. If everything is well done, it accesses the main functions of the application.
The next time it opens the application, it will no longer need to authenticate itself, it accesses directly.

Help me please …