Boot Camp won't go to Windows Install

Hi guys trying to use Boot Camp but for some reason it keeps taking me to the SELECT TASKS instead of going straight to the INSTALL WINDOWS where you get to change how big of a partition to use.

Installing:

WINDOWS 10

I have:

High Sierra Version: 10.12.2

iMAC Retina 5k 27-inch Mid 2015

So far when I checked the Apple support, supposedly my iMac should be able to just install without a USB or CD.

I dont have any USB or External CD Drives...so I really need help on this. Been researching everywhere and found nothing on what I could do to fix this.