How can I add a little gadget on the check out page once entering the payment step to say that this place is now secured ?

Hi Ahmed, the checkout page is one of those hard-to-customize pages. You'd need to do one of two things: 1. Find a plugin that lets you add custom items to the checkout page (this is usually fields so this may not be the best the option) 2. Go in the actually code. Once you installed WooCommerce, likely the files you can modify were added to your theme's folder. You'll need to go into those files on your server (always make a backup first) and modify the checkout page PHP file there. Hope that helps! PS: It may not be necessary to add that message as long as your site has an SSL certificate involved. You could use the store-wide notification feature and just have it show from the shop page that your site is secure. That may be the best option of them all.