No doubt there's a 'how to' out there. Back in the Bad Old Days (2009-ish)I had to use a special email non-amazon stuff onto my 2nd gen Kindle. I've not done it since then though I'm sure it must be easier now.
I actually need to look for a bigger e-reader. My Paperwhite doesn't do justice to a lot of the books containing maps and stuff. For those I usually end up having to resort to my iPad or Fire tablet. Anybody have recommendations on an e-ink reader with a 9" or bigger screen?