These are third party tools to work with the Wayfarer Map. We are not allowed to link to third party tools on the forum. If you Google search for “wayfarer tools”, the correct site will have a link to the Wayfarer Discussion Discord. There are many knowledgeable and passionate Wayfinders there, including many of the Wayfarer Ambassadors.
Historically, it has been observed that there are ways to influence which becomes the gym, but Niantic has called trying to do so abuse. This was discussed on another topic on the forum where staff did not choose to comment: From PokeStop to Gym? A showcase stop will not become a gym.