First the tour, then the gear.
I first toured on a 10-spd road bike, with a day-pack on my handlebars (straps wrapped over the bar, cinched-up in the center so my wheel could turn) that fell against my brake cable. I had to disconnect the front brake while riding and climbing, then - when topping a pass - stop, put the pack on my back, re-connect my front brake and ride down.
I had a rear rack, where I kept my sleeping bag and tent rolled-up under a foam pad, and bungeed it all together so my wet clothes could dry-out on top.
Sure, I looked like the Beverly Hillbillies, but I rode all over Idaho and Montana for as long as 3-weeks at a time and fell in love with bicycle touring. I also learned about what to carry, how to organize my stuff, how to plan a trip, how to climb big hills, how to eat on the road, etc.
Since you can't learn to do something without "doing" it, I say get on whatever you have, jerry-rig something to carry your gear, pick an adventurous route and hit the road. You will learn by doing and have many a tale to tell.
You've got the rest of your life to select gear. Get touring now and happy trails.