I can access the Sydney’ Princing Table into the customize menu, but I want this widget on one single page. Do I need a special plugin? I have the Sydney Toolkit. I need to insert the widget for a Page Builder, is my problem came because of a specific Page Builder?
As per your screenshot is showing, you haven’t yet activating the Elementor page builder. The Pricing Table widget along with other Sydney Pro’s native widgets are only available in Elementor.
So I’d recommend you use Elementor.