Your best bet would be to get yourself an agent and/or manager. Generally, you need a packet to do that (one will come in handy if you're pitching anyway), with a pilot or two and usually also a couple of spec scripts, though if you're entirely looking to pitch a series you might not need specs, the odds of getting a show picked up with zero experience is close to the odds of your first book being Harry Potter.
You can submit a script to Amazon Studios; they're open.
Netflix you likely won't get near without serious representation.
Mostly, you'd need rep or a job, though if you're hoping to pitch a series I presume you want a new job.
I *think* I read HBO has a writing program/internship/fellowship, like many of the broadcast networks do. These are very competitive deals you can apply to that, if you win, result in a writing 'camp' (whichever of the above they call it), for a couple months or whatever (usually in LA), and you may get shifted to a room job, which, eventually down the line could someday, if you're lucky as fuck, end up with a pilot in dev.
