A good way to 'dip you foot in' is by taking the time to learn the basics of the craft. To do that, you need the proper tools - give some of us who have been doing this for a day or two longer than you have for knowing that sometimes people just starting out don't know what they don't know, and our experience tells us that sometimes it's helpful to answer the questions that aren't asked as well as the ones that are. I don't suppose it occurred to you that when several experienced individuals tell you the same thing, there might be a reason?
Alright, to clarify what I know: I already know how to set up lighting for the particular things I'm interested in. I realize that it would be beneficial to pick up at the bare minimum a D7100 (if I'm on a budget) so that I can get 1/8000 of a second shots, as well as commander. I realize that if I start to take on paid work, I'll most likely need to have two camera bodies with me, and depending on the work my D5200 might be a bit lacking just on the flash limitations (though it should be fine if I throw something like an SB700 on it for commander). I realize that for particular kinds of work that I'll need various lighting equipment (diffusors, reflectors, flash tripods, multiple flash units, etc, etc). I realize for different types of jobs various types of things may be of use (black rapid, monopod, tripod, and other things). I could go on and on. I've watched countless hours of videos and read countless hours of articles, and I've spent many hours shooting. While that doesn't add up to making me a professional or ready to run a photoshoot, it still brings me up to a speed that most beginners aren't at in the amount of time I've been shooting. I've already conceded that I intend to continue shooting and learning for some time before I even start considering taking on a specific job.
I'm in the process of picking out a flash head for my D5200, and I'll be connecting it via a wire, so that I can do some single-flash off-camera photography. I find flash and lighting to be quite straight-forward in many ways... while there's lots to learn (bouncing light, controlling light, limiting light, throwing on filters to take the camera down a few stops while maintaining the same DoF, etc), I think I have a considerable grasp on it all.
I'm considering picking up a 17-55 in the place of my 16-85 now (for my own purposes: walk-arounds), though I'm also weighing the option of just sticking it out for a while and shifting to FX with a 24-70 f2.8. If I got into doing any shoots, I wouldn't have the cash for a Nikon 70-200 f2.8, so I'd either be shooting with a Tamron/Sigma 70-200 f2.8, and/or an 85mm 1.8G, depending on what I'd need for the telephoto/portrait reach end. I realize there's lots of different lenses for different jobs, I know what lenses are good for each job, I know that there is variation between each photographer and what they find works best for the job, and I know having multiple camera bodies can be useful for a job... etc... etc.
I don't particularly want to get into writing an essay on what I know, but that's just a little bit of it. While I need to continue working on how I frame my shots, as far as getting consistent shots in demanding situations, I have that down (of course I can use more practice and use different gear, but I know I am a consistent photographer at least without flash -- and I know the limitations and how to push those limitations given my gear and any particular scenario/lighting situation).
As far as editing raw files goes, I also need to pick up an IPS screen. I have worked professionally with Photoshop, so photoshop and lightroom are second-nature to me.