Help me appreciate calligraphy

This is a rubbing of Ma Dezhao's calligraphy "The Character "Shou" in the Sixties Chongzhou" in the Forest of Steles in Xi'an. The content of the postscript is "Yu You read "Shang Shu Hong Fan Pian", the five blessings are longevity, and knowing the collection of blessings means longevity. In the spring of Jiazhi, I saw the old traces with ninety-nine and twenty-one combined as the character longevity, and got "The sixty-year-old Jia is very similar to the Zhou Dynasty. Although the stippling is not done well, I know the meaning of Jiangxian's calendar." The upper paragraph is "Tongzhi Jiazi Zhongchun", and the lower paragraph is "Xishu Ma Dezhaoshu".