If you want to practice hard-pen calligraphy well, you'd better use a pen for two reasons: First, most calligraphers write hard-pen calligraphy with a pen, so there are relatively rich things to refer to. If you use a pen, there are very few copybooks you can refer to; Second, the quality of pens is much better than fountain pens. Generally, pinhole fountain pens can't reach the beauty of simplicity in calligraphy, while other fountain pens similar to ballpoint pens are even more difficult to control. If you are a beginner, you should stick to it and write in block letters with a pen.
I still want to accept what the family says. Thank you very much.