Is it important in Islam to categorize yourself as Hanfi, Shafi, Shia etc. or we can stay as Muslims only and can follow anyone at anytime. I asking this because I usually believe that we can follow any fiqh at any time. And what about the hadith in which He (peace be upon him) has talked about 73 sects i.e. Holy Prophet ﷺ said: "Indeed the Children of Israa'eel split up into seventy-two sects (72 sects) and my Ummah will split up into seventy-three (73 sects), all of them are in Fire except one."It was asked, "what is the one?' He said, "That which I and my Companions are upon."
Tirmidhi 2641, Al-Haakim, 1/128-129, Imam Ibn Hajr in Takhreej Ahaadeeth al Kashaf.