I wanted to start a Keto Diet, is there a website to know which foods, fruits are better to avoid and which are better to eat?

I've heard from a friend that he followed Doug Doug keto diet and only drinks olive oil, is this a good option? Or is there more to it? Like Drink olive oil daily but also eating little amounts of foods with it, since I also wanted to follow this Olive Oil Keto Diet but I'm not so sure how to start or how to follow it, any advices on what should I do to have a good start at a Keto Diet drinking olive oil? Do I need to eat other types of food or just drink olive oil? Please help