Hey @Killian_L Welcome to the forum!
It looks like all of your DNS records have been set correctly. However, this issue is due to not having the www version of your domain set as the default.
If you are using A records on your root domain, you will need to set the www version of your domain as default to use SSL and your site to function properly.
- Head over to the hosting tab of your project settings
- Click Make Default next to the www version of your domain
- Click the Publish button at the top of the page, make sure the checkbox is checked next to your custom domain (now the www version), and click Publish to selected domains
Once you make that change and publish your site should function as expected.