explain because i haven't heard of any of those things
aka i'm dumb
soft bricked: bricked, but you can restore and you're fine (what you have)
hard bricked: doesn't' even turn on or doesn't show even the oem logo, aka you're forgeted
sideload: where you plug your tablet in and then load a rom from your computer, its under advanced iirc. I believe safestrap has it since TWRP does
I don't know jack stuff about kindle tablets so this will be fun to try to help