I wouldn't worry about a guide. There is no substitute for experience. Just start small for your first trip (both in time and distance).

Try this to start. Camp in your backyard. Load everything you think you will need in your backpack and then cook dinner, eat, clean up, sleep, cook breakfast, eat, clean up, and repack. This will help you figure out if you have everything you might need. If you have to go into the house at some point then you must have forgotten something.

Next step is to go somewhere just for one night. Preferably not too far from civilization (where you cell phone still works and you can call if you are in trouble).

I would do the same to build experience in adverse weather. Purposely go out in your yard or a nearby campground on a day when rain is forecast, or on a day when it is going to get pretty cold. Learn what can go wrong and what to do.

This may sound silly but it's what I do. Every time I get a new piece of gear I try it out in the backyard. My first time in a bivy, my first time using a tarp, and my first time in a hammock were all backyard trips. My first time under a tarp in the rain was also in my backyard. I want to fuss with my gear in a controlled environment so that when I go out on a real trip I have some confidence in myself and my gear.

The same principle applies to hiking. Go on a fairly long day-hike with a fully loaded pack (as though you were going for a few days). Go 5 or 10 miles in or so in a loop that leads you back to your car. You can't know if your pack and clothing are comfortable unless you've gone a few miles in them. This will also give you experience with how to pack your pack, how to use your trekking poles (if you are a pole person, not everyone likes them), putting on and taking off layers of clothing as you need them, etc. Even though it's just practice it will still be enjoyable. A 5 or 10 mile hike into the backcountry is enough to really begin to enjoy the outdoors and the freedom of backpacking. (Be sure to stay hydrated on this hike, it takes more water than a beginner guesses that it will. Also bring plenty of snacks. Hiking 5 or 10 miles burns a LOT of calories and you'll start feeling weak if you don't refuel.)

Build your experience that way. Soon you will have the confidence to go a long distance on an extended trip.

Have fun!

Heber