help with bootcamp windows installation

so i put my usb in my mac to installl windows software , but it says to remove external hard disk before continuing bootcamp , but then shows error while installing windows software in the main storage ... my mac is a 2017 macbook sir ...what do i to

pls help

i suggest youtube. and if that doesn't work, remember my psych major blonde gf figured it out without any issues. so no pressure.