Excel does not provide a tool to directly change the default font color.
You can do it in another way.
For example, if you need to set the default font color of excel to red, you can set a red font template:
1, open a blank worksheet.
2. Press CTRL+A to select the whole table and set the font color to red.
3. Save as. The file name is template 0 1. Select the template as the save type and save it.
4. Open EXCEL and click File/New/Template 0 1 to call the template with the default font color of red.
In this template environment, the color of the text entered in the worksheet is automatically set to red.
This can indirectly change the default font color of excel.