Is it better to practice hard-pen calligraphy by buying copybooks or attending XX hours of training classes?

Or buy a copybook and copy it slowly according to the copybook. At first, it is slow and slow, so the effect will definitely be better. If you practice to a certain extent, you can ask your friends around you to help you see if your writing is not good. Sometimes you can't see what you wrote yourself, but others can see it at a glance.