You can add a zero before a number in Google Sheets and Excel using this tutorial. You need to change cell formatting or use function.

How to subtract in Excel using cell references You don't have to subtract numbers in a single cell; you can also set up a formula that will subtract the values stored in multiple cells.

Excel filters help you find exactly what you want, no matter how big your spreadsheet database is. Here's how to set number, text and data filters.