I see that your understanding of how switch CFW is ...........?
fusee.bin is the payload you send in order to run CFW
how ? there are many ways to do it here is a few. with a dongle, with your pc using tegrarcmgui, and also using hekate, from your phone and prom a raspberry pi.
why ? because if you dont you cant have CFW unles you use pegasus but thats another topic for some other time.
if you are confused look a my profile then look at my threads and read the how to update firmware guides