widget on all the places of the website except for the contact page.

Hi, I am developing a WP website with a theme of elegant themes named Fable, my question is how do I put out a widget only on the contact page? I want this widget to be displayed on all the other places of my website. I searched on the forum but the answers don’t work for me or i don’t know how to apply them.
Here is the URL: https://anasanchezterapias.com/

Say that I started with WP a few weeks ago and I’m not used to it yet.

Thank you for your time.