question #1 Sahih Muslim 692a, Book 6, Hadith 15 : What is the significance of following the actions of the Prophet Muhammad (ﷺ) in Islamic practice?

I went along with Shurahbil b. al-Simt to a village which was situated at a distance of seventeen or eighteen miles, and he said only two rak’ahs of prayer. I said to him (about it) and he said: I saw ‘Umar observing two rak’ahs at Dhu’l-Hulaifa and I (too) said to him (about it) and he said: I am doing the same as I saw the Messenger of Allah (ﷺ) doing.