If you are trying to write a number in Excel or Google Sheets that starts with zero (0), you may not do that due to the default settings. In that case, you should follow this tutorial to enter zero ...

When you type a seven-or-ten-digit phone number into an Excel cell that uses the phone number format, Excel will automatically change the way the number looks so that it appears as a phone number. If ...

Adding a text to a cell in Excel using Formula requires use of ampersand operator, CONCAT function, or the LEFT, RIGHT, and LEN functions.