Hello Rafael,
welcome here. Very nice topic for the theses 🙂 . To get some basic clue, you can find all the basic info in the links on the left side of the page. Than I would recomend to go through the article section and methods forum. Of course if you need explanations post in the forum, there are lot of people with extensive experience who can help you. To get the fish, please go to https://www.parosphromenus-project.org/en/distribution/suchen-sie-fische.html
Hope that helps for now, Pavel