I recommend not doing HDR!
(Har har, I'm just being cheeky. But I really do hate it. 99 times out of 100, it's way overdone and looks like crap. And I cruise many many photography forums. So if you insist, make sure it doesn't look like crap)
But yes, first learn your camera. A new lens won't do anything for you unless you know the ins and outs of how to use your camera body. The D3200 has a limitation that will effect your choice of lenses - it doesn't have it's own autofocus motor. This means you'll have to buy AF lenses ($$) if you plan on using AF.