So it took me way too long to figure it out, and I had the tablet lying around. The tablet is a SM-T550, make sure to install Heimdall’s GUI and get the certain file, and then the instructions are really straight forward. Sorry if the instructions aren’t super clear, I did do it a while ago and I remember lk2nd was a pain to install. The wiki stuff: wiki.postmarketos.org/…/Samsung_Galaxy_Tab_A_9.7_…