You need to pick your budget and expectations. I bought a
Syma X5C-1 from Amazon, 4 extra batteries/charger, and some spare parts for $80 total. It's a lot of fun to fly. I haven't even used the camera yet, which I know is of very low quality. But it's a great beginner quad.
A friend of mine had something even smaller to learn on. Now he has ta DJI Phantom 3 with 4k camera, case, extra battery, etc. He has about $1500 invested. Flying his a a very different experience than mine. Mine is focused on the technical control of flying. The power and range are low so you can only get into trouble as far as you can see it from the ground. His is a lot easier to pilot, can go one mile+ away while streaming to a smartphone/tablet in real time. The GPS based systems will hold it in one spot with wind compensation, or even if you can push on it at 6' off the ground. And there are many options between and even higher prices.
I recommend picking up a toy to start with. Under $100 for a lot of fun. You can learn a lot of basics of flying them before deciding how you might want to spend on a better one.