Question GPU box

I want to understand what is considered a "sealed package".
Understood. Yes, the box should be sealed like the picture you posted. Some may also be shrink-wrapped with clear plastic, as well.

Inside the box, the GPU itself may (but not always) have a seal on the anti-static bag the GPU likely ships in.

I have seen GPUs without the anti-static bag seal, or even the anti-static bag. This can vary.