I am not sure how many others got started with bike touring.
I did not begin with a long trip. I began with multiple short trips of two or three days biking (plus the time to get to and from the trip starting point).
As I rode, I also began to determine what stuff I needed to carry along to meet my needs.
Now, before any trip, I open up one of my panniers, remove the moth balls, placed there to keep the mice out, remove the check list I have and then gather the stuff I need and set off.
After a trip, I clean and repack my panniers.
I also keep a log of most of my trips. The log included things I think I should add to the stuff I carry, but might need on another trip.
For example, I carry a small container of LokTite. That stuff helps prevent screws from coming undone. It is a very small bottle and fits in one of the pockets of my Arkels. The times I have used it have been worth time trouble to carry it.
Same goes for my water filter system, my 10L MSR water bag, my roll of black electrical tape, etc.
Back to the point. Begin with short trips, of a couple of days and then grow into the fun and pleasure of bike touring.
Another point. Having my wife (or daughter) with me has been an asset. People are more willing to talk / help a couple than they are a single male.
Still, people are very friendly to most of us on bikes and will often let us camp in their front or back yards.
Enjoy,
Tom