If you are a junior high school student or an adult with a certain foundation, you can teach yourself and learn from calligraphers online; If you are just learning to write, you can choose to sign up for online classes, worship famous teachers, or sign up for calligraphy classes, so that children can lay a good foundation in calligraphy.
Which way of learning depends on your learning purpose. If you just want to improve your usual writing effect, so that your writing style is not too ugly, and you don't want to spend money to learn, then I suggest you choose a free learning method.
If you regard calligraphy as a hobby, you want to write well or even well, and you don't care about spending money, then I suggest you take a calligraphy class. Under the guidance of the teacher, you will quickly master the writing skills and improve your writing level!