Functionality:

1. User can add as many product as he can.
2. On clicking on Proceed with amount button it will redirect to payment page.
3. If user enter the opt: 123456 the it will redirect to payment success page else payment failure page.

User Interface:

1. If no item is added in cart the the Proceed with amount button is not visible as soon as user select any product it will Proceed with amount mentioning total amount button will visible.
2. After clicking in Proceed with amount button it will redirect to otp page.
3. Here user can fill all their details and verify OTP.
4. After checking OTP it will redirect to success or failure page accordingly.