Wow, you're an easy mark... Fakes nowadays can look nigh identical to legit items. Even buying stuff shipped/sold by Amazon can result in you getting fakes (Amazon obviously sources their stuff from legit sources, but warehouses reship 3rd party sellers stuff and don't sort their inventory separately (so you can also get legit stuff from known fake sellers off Amazon, lol))
Edit: Oh, and you can still get hit with counterfeits on B tier brands. The quick test is if you're getting read/write speeds in the expected ballparks. Something like this Kingston is probably adequate, it has reviews to show you what to expect (and isn't covered with comments about fakes). You can find faster better drives, but you'd be paying more than like $20 then
https://www.amazon.ca/Kingston-Digit.../dp/B016BEPP9O