trying to make a persistent usb for parrot security 4.5.1

I have been trying to make a persistent usb for parrot security os 4.5.1 apparently the youtube tutorial i have been using is outdated (linked below) if anybody could tell me what i'm doing wrong here that would be great, i'd love to get this linux distro up and running and start learning https://www.youtube.com/watch?v=8EQfn3KbFMs (the video at the time of this posting is 8 months old)