So, you are a newbie and wanna start your designing career with Autocad.
Than yes you need this while you are opening your CAD.
Often user got confused with this auto start option.
To avoid this, Just type the "STARTUP" at command line and enter the value 1 to show dialogue box while starting up the Auto-cad or go through the new file tab.
Now choose new, or simply close the Autocad and start it again.
You will see the miracle.
You can start now with Metric or imperial setting, or by choosing the template and even able to open the previously build drawing.