I bought an Tenkara USA 10' Iwana rod years ago! I love it for small streams, like the forks of the Snoqualmie and stuff up high on the Skykomish, like the Tye and Foss..
I usually start with the Tenkara or my 6' 2wt 4pc that I built. I love that it's easy to carry the tenkara rod, it fits in my wading rain jacket or even my sling pack. A small box of flies is all that you need.
It's easy enough to learn, and it should come with a floating line at least. You can buy other lines and I shoot for a line about 1.5 times the length of the rod. You do have to be careful when extending the rod and putting it away. Many newbies break the tip right away.
It's easy to cast, just a slow short cast! I'm sure there are plenty of good videos, but I just learned by fishing it and from a friend who got one at the same time I did. Don't overthink it!
I usually use a small dry or nymph.. I have tied a few tenkara flies and they're easy to tie, but small flies challenge me these days with my eyes and the neuropathy I have. Don't get old! LOL!