Add A New Badge for Products In My Dawn Theme Version 8.0.0

[KornerLabs]

Hello guys, My first time here posting, I hope I'm writing this in the correct section. Here is my question (I dont speak really good english): I've been looking at tutorials on how to make a new badge appear on certain products (such as Sale or Sold Out) but using tags. From what I've seen, it's done by editing the code but all the tutorials I've seen say that I have to modify a product.liquid but I don't see it. I have Dawn 8.0.0 and I want to know how to do it. My tag I'm going to use is called 'presale'. I leave some screenshots of what I get in the code with the word product, to see if you can help me to write the code in the right place, I do not understand very well of liquid (only CSS).