Did I Back Up My Kindle Right?

So I don’t know how you’re SUPPOSED to do it, but I’m switching to my mom’s kindle account and I want to keep my stuff so I was too lazy to look up the proper way to back up a kindle fire, so I connected it to my computer and when the folder opened up I copied everything onto the flashdrive which I always wear around my neck because it has all my favorite things on it So yeah now when I switch will I have all my stuff? Like can I just delete everything from the kindle then paste this stuff and it will be fine? Also how much information was on there because my flash drive is only 8 gb. (they don’t make sexy flashdives in 16 gb models apparently, tsk tsk)