Finalize Website-MS SQL Integration

The site is already built; what remains is wiring it cleanly to my MS SQL backend. I need two concrete pieces finished:

The API has been done, it just needs the final touches - this is a very quick job.

• User authentication must pull credentials from the User information table, create secure sessions, and gracefully reject invalid log-ins.
• All existing data-entry forms should insert and update rows in the Form submission table, with solid input validation on every field and basic data-integrity checks before anything is committed.

A simple, well-structured DAL or parameterised query layer is fine—I only care that it is secure, easy to follow, and throws clear errors if something goes wrong. Once these final touches are in place, the site should compile and run without warnings, and I should see new records appear instantly in SQL Server Management Studio when I test each form and log-in path.