Actually, it totally depends on how much time you can devote to your studies. If you are ready to spend a healthy amount of time, then you can learn Tableau in just one month. Now, let me tell you something which will help you further. As a beginner, first, you must know the basics of SQL because it is going to help you a lot. After that, you can take up a Tableau Training Course and follow its curriculum. And boom, you have learned Tableau in 1 month! I am sharing a video tutorial, which can help you learn Tableau in a shorter time.