Which diet(lifestyle) is the best?

Sabine

Hi all! Im gonna start going to gym this week. And im not sure wich diet should i go with. Last year i lost weight while sitting on low calorie diet. But it was all boiled food and i cant even think about it. Then in december i started keto, and i gained 15 kg , i just don’t understand keto. i thought that i did everything they were asking to. And now im scared to start it again. What options do i have?