To add hyperlinks to Excel, you can type the corresponding URL, add hyperlinks using the Link feature or use the HYPERLINK Function.

If you want to add a header or footer to all sheets, select every sheet by right-clicking one of the sheet tabs at the bottom of the Excel screen and clicking "Select All Sheets" in the pop-up menu.

You can insert or add Header and Footer in Excel spreadsheet using this tutorial. Insert page number, current date and time, etc.

You can use Excel, Microsoft's spreadsheet program, to store, organize, and analyze data in a number of ways.