I just want to practice official script.

But you can, but it depends on what purpose you practice for. If you want to learn calligraphy, you can learn it at all, because regular script is originally evolved from official script, so it is easier to master the foundation of calligraphy and lay a solid foundation for learning other characters in the future, so it is easier to learn other characters, but this process is long and requires time and patience to learn; If it is for writing at ordinary times, I suggest that it is better to learn regular script and running script instead of official script. First, it is more convenient to write; Secondly, people usually write regular script or even running script, because it is faster and easier to identify. Nowadays, regular script can't adapt to the rapidly developing world, let alone official script, because calligraphy has developed step by step from official script-regular script-running script-cursive script. So as to adapt to people's efficient life. This is to learn according to your own situation. Finally, I wish you early success!