I wanted to put the Last Topic Widget in my front page with just the forum "news" so that when I make a new news in this forum it will be shown on the front page entirely.
Is it possible ? If yes how ? Sorry, I tried to search online but I'm a big noob with this widget and I'm french too sooo...
You should search for ways to add WordPress widget in the page content or in the home page sidebars. This doesn't have direct relation to wpForo. This could be done using WordPress native blocks or some plugin. Here is an example of adding widget in page content: https://www.wpbeginner.com/plugins/how-to-add-wordpress-widgets-in-post-and-page-content/