Yes, you can change the theme of your site by yourself choosing one of the themes available for Wordpress.
Keep on mind that each theme has its own features and functionality, so changing the theme you will need to verify that everything is working properly on your website.
NB: If you have the Easy Commerce version with Storefront theme, changing the theme you will lose the automation available on the 'Brands' page
If you need assistance with the installation and configuration of the new theme, make a request to our technical department. This request is not included in the Easy Commerce service and will be subject to additional pricing.