To change your PHP version first you need to:
1. Access your file manager or your FTP account.
2. Navigate to the folder where you want to change the PHP version and create or modify the .htaccess file.
3. Edit your .htaccess file and add this code:
The second line is what defines which PHP version your folder will be using, here is a table for reference (lsphp56 means PHP 5.6):
Save your file and just run your website using a subfolder address or subdomain. Ex:
If you want to test if the code was applied, create a new file named phpinfo.php, add this code and save:
// Show all information, defaults to INFO_ALL