Installing an older version while keeping your current data requires a careful process: Older versions of XAMPP (Windows) | Uptodown
Great for WordPress – easily switch PHP versions (5.6 to 8.2) from the UI. xampp download old version
Then browse by version number. For PHP 5.6, you want XAMPP 5.6.40. For PHP 7.0, look for 7.0.33. Installing an older version while keeping your current