Which radicals should we start with in learning hard-pen calligraphy?

Tracing red and copying famous copybooks starts with strokes, that is, radicals. My method is to break the basic strokes and radicals one by one, not the copybooks written in the market. Not so good. You just need to buy a basic copybook. Don't buy articles with many repetitive words. Personally, I prefer Pang Zhonghua, so I choose copybooks according to my own preferences. Just practice a few radicals and simple words every day, remember not to write more. You can't write too much.