I've been using XDA as a source of invaluable information for years. I've done lots of stuff with the help of this forum, for which I'm grateful. Now it's time for me to ask a question or two.
Are you trying to recover what's on it or starting from scratch? I imagine first step is downloading TWRP and having Odin install it. I have this tablet and recently installed LineageOS MicroG and I feel it is much better without the heavy Gapps installed. Just my opinion, has been working great so far.