You're getting good advice here. I'd start with a few car camping trips just to get a sense of what it's like to sleep on the ground, live in a tent, and cook with no refrigeration. You don't need different equipment, just a tent and a sleeping bag--but by car camping you give yourself the option to bail if things aren't going well--something that's a lot harder to do when you are backpacking. Even your backyard is a worthwhile experiment. (You'd be surprised to know how many of us veterans here try out new equipment or techniques in our backyards!)

It's a pretty simple transition from that kinds of camping to an overnight a couple of miles in from the trailhead. And once you do one or two of those without any problems, then the only big change for a longer hike is that you have to carry more food, and you have to go longer before you get a hot shower.

And as many have mentioned here, if you were hiking "solo" in many of the major parks, you'd still see between 15 and 50 people a day on the trail, and probably camp near another group each night. If you're worried about the wilderness, that might be comforting.

Take it easy and slow, and have fun. We'll see you out on the trail in no time.