I suggest you practice with a brush and a hard pen, which will get twice the result with half the effort! Practice Yan Zhenqing's Diligence Monument in regular script, and select Wang Xizhi's Preface to Lanting and Preface to Saint Education as the running script. If you just want to practice pen writing, you can learn from Qian Peiyun, which is faster. If you practice every day, you can write it in a month. -But it's just a shape. It takes many years to look like it, but it depends on understanding.
Remember to write like that even if you want to practice writing!
Pen writing and brush writing seem to have nothing to do, but practicing together will improve faster!
Come on!