The fastest way to checkmate is 2 moves also known as the fool's mate.
another way is the three move checkmate
And the most famous way is the 4 move checkmate also known as scholar's mate
I assume that you are new to chess as these are taught to beginners very early. But still if you have any other questions, Then please feel free to ask.
please note that you will not see this in regular games.
also, this is my own game in which I gave a mate in 6 moves!
Hope this helps
What combinations of pieces can u checkmate with and which u checkmate the fastest with?