1. Open the toolbar and click on "Select Files".
2. Choose all the photos and videos you want to change dates for.
3. Go to the toolbar again and click on "Change Dates".
4. Select the "Derive from file names" option and enter a file name format.
5. Review your file names and customize the file format string that matches your file name format. Please reference the examples provided.
6. Click on "Apply" to proceed to derive dates from file names.
7. Finally, go to the toolbar and click on "Save Files" to save files with updated dates.