Thank you for using free version.but the option you are looking for is not present on the free theme, but what you can do is you can add this option by creating a child theme.
to build a child theme for the parent theme,
Thanks a lot, please can you confirm me if i have to uninstall the old theme to install the new pro version? or it will be like a new theme? thanks in advance, i will buy the Pro. Hope that if i have more needs your support will be as quick as here 😀