It depends on your experience in programming. If you are a complete beginner in the field of programming, then it will take three weeks to learn R programming. After that, you can master the use of R programming by working on different types of data and learning how you can use R programming for statistical analysis and data visualization. It is completely on you how much time you will invest in working on datasets. Next, if you have prior experience in programming, then you can learn the basics of R in one week, practicing 3–4 hours a day.