Hey there! I can definitely help you with that.

When you protect a worksheet in Excel, all the objects on the sheet, including text boxes, are automatically protected as well. However, you can unprotect a specific text box by following these steps:

1. Right-click on the text box that you want to unprotect.
2. Select "Format Shape" from the drop-down menu.
3. In the Format Shape pane that appears on the right-hand side of the screen, click on the "Properties" tab.
4. Under "Protection," uncheck the box next to "Locked."
5. Click "Close" to close the Format Shape pane.

Now that you have unlocked the text box, you can edit its contents even if the worksheet is protected. Just make sure that you re-protect the worksheet when you're done making changes to ensure that the other cells and objects on the sheet remain protected.

I hope that helps!