Excel sheet

I'm looking to create an Excel sheet to help me organize my medical coding data in a specific format. I have a detailed plan in mind for what I need the spreadsheet to do, and it requires a significant amount of security to protect the data. With this in mind, I would like to enable password protection for anyone who attempts to view or make changes to the spreadsheet. The look and feel of the spreadsheet should be professional and be able to handle a large volume of data. Feel free to suggest any modifications to the format or layout that you think would be beneficial to the project.