What is start in the task manager?

Hi, I just saw there was a program or something called start. This program has NO file path to call (it is grayed out). Can anyone tell me what that is? Because when I started my laptop, a window came where the icon was a bit black, like the program icon satrten and there was something with windwos, execu… It was gone quickly, so I couldn't see or read it. The program "Start" looks like this

Does anyone know what it is and whether it is dangerous or something?

Right click on it → Properties, tab General and Details…

In any case, that is not part of the system.