I'd still recommend planning overall area->area map, but yeah, improvising what road to use for each place can be good
always keep an eye out for fire roads and rail service roads, they're really fun, take you through some nice places, and aren't that much slower to ride than asphalt. they're all over the place too if you look carefully.>robbed
this is going to vary a lot from region to region. if you're out in the country in the US, there's very little chance of anyone messing with your stuff. that mainly is an issue if you're passing through cities. country people tend to be chill af, don't be suprised to see people offer you food or water as you pass through small towns.
this becomes a much bigger concern when you're in south america or central america, depending on the region. again, in the countryside you'll be much safer than in cities, but keep a lookout always. if worst comes to worst, hiking is always an option.
also, its hard to do, but don't get too attached to your bike. all bikes go on to bicycle heaven someday, it isn't the end of the world when something happens to your bike as long as you keep riding.>comfort>clothes and tent shit to start off with
DON'T DO THIS. buy good, reliable camping gear, and if you have to buy a slightly cheaper bike, then do it. a good pair of cycling shorts, a jersy, and a good tent, mat and sleeping bag will make much more difference than spending an extra $500 on the bike.
also, bring a tarp with you at all times. it took me a while to figure that out, but even a $5 blue construction tarp from home depot is incredibly useful as it'll allow you to keep your bike dry at night, your bags dry, and can be used as a second tent footprint on rough ground>components
you'll get the hang of it over time. don't worry too much about most of it, modern bicycles are incredibly capable and pretty much anything can work. There's some great resources online to learn about this.