What to buy.

I have been buying heaven scroll at my bestbuy in the booster pack format recently. And wow I love these cards the quality the effort it’s really top tier stuff. I’ve always collected sports which if you know anything about those is the opposite. Naruto is my favorite anime by far and I really just enjoy collecting these cards which is refreshing. What boxes should I be buying for best bang for my buck I’m seeing a lot of tier (insert number) wave (insert number) Chinese boxes on eBay for like $25 with 20 or so packs which seems like a steal compared to what I’m used to buying but not sure if that’s actually good or not. Also I read through a tier list on here of rarities explained and I’m so lost on the boxes (ninja era, pre ninja era, post ninja era) it made no sense. (The post seemed well done just my newness to this threw me off) can anyone point me in a beginner direction with understanding waves, releases, box types, etc. as well as recommend what to buy? Thanks!