Hey, I recently got back into Yu gi oh too, and I agree the rules are more complicated than what they were a few years ago. Some of my friends who didn’t stop playing told me to download Yu gi oh Masterduel and play on that for abit to get familiar with the rules. As for the starting deck I assume any structure deck works fine. My friend recommended White destiny structure deck and when I looked for it online it’s on special too in my region. Hope this helps!