You know, maybe it really isn't so deep, or profound, or bloody difficult as everyone seems to be making out. You can spend far too much time debating, agonising, and philosophising over this stuff, and in the end it is all really a bunch of crap. What does it matter if photography is art? Personally I prefer to think of it as a craft, it takes all the pretentious nonsense right out of it.
So if you can get hold of that concept, of craft, the natural conclusion is that you should get out there and master your craft. Whatever floats your boat - portraits, landscape, street, or still-life, just get a camera out (any camera will do) and get on with it. Shoot lots, be very critical of the results, go out again and do it better.
And when you get something you really like, don't give a monkey's whether it seems to be art or not. Or whether anyone here on LL Forum likes it. And especially disregard whether or not John R Smith likes it Print the sucker, pin it on the wall and enjoy it.
If it's not fun, it's not worth a damn and not worth doing.
(Apologies, Alain, we cross-posted. This was not meant to be a personal go at you)