Need a codee

Have a assignment that needs a live login page. With OTP login, and on the backend a random but unique (key) user_id needs to be generated. With phone number mapped to it saved in any right type of DB (Also need to know why we are using the particular DB). The front end can be simple with just the phone number and "get otp" button. 2nd landing page needs to have an option to type OTP (/autodetected from msg)

Once OTP verified, good to go. Just a native prompt for success would do.

Need the code and walkthrough of the code for this assignment. Documented would be even better!