I'm looking for a TV which allows me to use apps like Prime Video and Netflix. Do I need a Smart TV or what exactly do I have to pay attention to when buying?
Either a Smart TV or you buy an Amazon Fire TV. This makes every TV in principle a smart TV
You either already have these apps on a Smart TV or you can get the Amazon Fire TV Stick, which also has Netflix, Amazon etc.
Just buy a Fire tv stick, but most televisions should have smart tv these days. Ps: recommend you synonymous directly to buy a 4K TV worth the more and is not much more expensive than Full HD