I find there are always a tonne of games to join at any given time on the "Play Now" page. I just join and see how the chips fall. Routinely I'm riding 50-100 open Turn Based tables simultaneously.
For OP: Stumble through the tutorial and join the game anyway. In Turn-Based I find most (all) people are very accommodating. Just write in the notes that you're a newb and don't know what you're doing. Most people don't care, and you can stumble along anyway, even go overtime without getting kicked out, as I do often/many times. Just push some buttons and play the best you can until you get a few reps under your belt.
It's obviously more difficult to learn Turn-Based and digitally, than seeing it in real time at an actual table. It's hard to see what your opponents are doing by reviewing the logs. Who cares? Just play, have fun, revisit the rules and a few Youtube videos, and the magic will happen.
Most importantly - ignore the haters, and the kickers - they are generally few and far between.
FWIW: I'm still afraid to join some big games I want to learn like GWT, Twilight Struggle, and Watergate.