PHP Application & Database (Advice & Development Support)

Just a brief on the project. It's a final year university project that revolves around digitizing the class signup process (by turning the paper-based forms and process into an online one. There are two UI's, where one is for teachers to approve the signup process and monitor responses as well as another for students to fill out the forms and submit them for approval.

The support is needed on the backend including the database (which is built on PHP). Optimally, your role would be to provide advice on how we can proceed with the development of the application (by answering any questions we may have on building the application) and overall development for some aspects of the application. Specifically, we need help in the development of the database (PHP Based) and linking it to the backend application.

The application itself is pretty straightforward and so would the support required, nothing too asbtract or difficult. Also, we are on a short deadline (April 1st submission) so we need you to be available for the next 2 weeks.

I compiled some initial Q's we had about the project (should be an indication to scope of support needed):
1. How can we connect the login page with the DB to recognize user credentials?
2. What is the code we can use in PHP to insert and request data from the database
3. What can we do to transform data from one user to another?