PDF Sending Certified Email Automation

I need a small application that reads an Excel sheet and dispatches individual PDF files through PEC (certified email) using the REST endpoints documented at https://openapi.it/prodotti/pec-massiva-api.

How it should work
• The Excel file contains four columns—Name/Company, PEC address, PDF file name, and email subject.
• Each PDF has a unique filename. The tool must pick the correct file and pair it with the matching row.
• Source files may reside either on my local machine or in a cloud folder (OneDrive, Google Drive, or similar). A simple configuration option that lets me switch between those two sources is fine.
• For every message sent, the system must save the PEC response and display real-time status (queued, sent, error, delivered).

Deliverables
1. A script or lightweight web app that:
– Reads the Excel sheet.
– Authenticates to the PEC Massiva API.
– Sends each PDF to its corresponding certified address with the specified subject line.
2. A minimal interface or dashboard showing the send log and current status of each email, with the ability to export the report to CSV.
3. Clear setup instructions plus commented source code so I can maintain credentials and endpoints myself later on.