So I suggest that the order of learning is to learn brush calligraphy first, and then learn hard pen calligraphy. If you learn hard pen calligraphy first, then brush calligraphy, the promotion of brush is not great. We know that hard-pen calligraphy is developed from Chinese calligraphy, so the nutrition of hard-pen calligraphy should be absorbed from Chinese calligraphy, especially regular script. There is a difference between hard pen and brush calligraphy. Where brush calligraphy is relatively difficult to write, it is much easier to write in hard pen, because hard pen is not so particular.
This is determined by different tools. We don't need to pay attention to many things such as soft pen calligraphy when learning hard pen calligraphy, because hard pen calligraphy emphasizes practicality, and there is no need to emphasize ups and downs like brush calligraphy. So it is much easier than calligraphy. Therefore, writing with a brush is good, and writing with a hard pen is naturally good.