Simply click on "Website", in the sidebar of your Amenitiz administrator area, a submenu will appear below and you can click on "Website".
Then click on the "Customize" button at the top right of your screen.
You will arrive by default on the home page.
All you have to do is click on the "Pages" button, located at the top of your screen in the horizontal bar. A sidebar will open giving you access to all the pages of your site.
Click on the name of the page containing the block you want to modify, and it will be loaded into the editor. In the sidebar containing the blocks on the page, select the block you want to edit.
Click on the "content" section, and you can modify the text of your block: