Hello, @Blade,
I have just checked your site now on GTMatrix and this is the result: https://gtmetrix.com/reports/ozando.fr/YBRk0iST/
If you can check below, you can see that your initial server response time is high: https://postimg.cc/RJnFy2pW so you have to reduce it, you can ask your hosting provider for the best plan they have.
You can read and follow the instructions written in our theme documentation about the speed of the site as well: https://xstore.helpscoutdocs.com/article/100-how-to-speed-up-my-website
Read these posts about DOM https://docs.wp-rocket.me/article/1412-avoid-an-excessive-dom-size https://isotropic.co/avoid-an-excessive-dom-size-on-your-wordpress-website/ Edit your page and Product elements and enable Lazy loading for the Product elements. It should reduce the DOM structure. Also, you may try to reduce the DOM results on the page by reducing the number of sections of the page/elements in the footer or header.
Furthermore, you can follow the instructions the speed testing site provides you.
Regards 8Themes Team.
