Student at the ENS in Paris, and questioner in preparatory classes, I decided to give physics-chemistry lessons to pass on what talented teachers have taught me and which I consider effective in order to help new students to better understand, learn, and pass their exams. Together we will work on the lessons as well as classic exercises in order to both understand and manipulate the key notions and concepts in the program. Understanding, method, efficiency, are the key points of my approach. I will adapt to each person's level, and we will be able to go back to the basics as well as go in-depth with the courses and prepare for the most selective competitions. Give real meaning to the course, to the formulas, to the calculations, to make them your own, to have a perspective on the results, to know how to present them clearly, to understand the logic of the exercises, all these notions are all points evaluated in the exams/competitions that we will prepare together. Courses possible in Barcelona (preferably in the city) or by video