How newbie friendly is this? Looking at the touch edition specifically. Do I need to know crazy info about tactics? Can it be played casually? Are there difficulty levels at the beginning? Or is the difficulty tied to the team you choose (ie juventus easy win in serie A vs a torino). Debating to try
There is no difficulty level, it's a total simulation - so if you have the better players it's easy, if you have poor players, you have to play for a draw and/or hit the other team on the counter, while using your training / transfer windows wisely to build your team's strengths over time.
The full PC version is incredibly complex - the "Touch" version less so, but still pretty deep. If I were you, I'd play the mobile version first, which is much much slimmer (tactics are much easier to tinker with, you have several aspects to tweak and they're mostly "on" or "off", whereas on the others each option is a slider of how aggressively you want to implement each instruction, plus deep individual player instructions that can completely change the shape of your formation without realising it, destroying the integrity of it).
I've ended up playing the mobile version (which has a pretty decent 2D match engine now), just because I can play it in five minute bursts and move through seasons in a week or two, whereas on the full version it takes me one real-life season to get through one in-game season, because one match takes me about 30 minutes of tweaking. I never get time to sit down with the PC version any more, so it's just sitting there.
But that's my favourite bit - and the most realistic bit, for me. Seeing what's going on as the game evolves, taking out the opposition's strongest players / instructions by reacting to them, and changing the flow of the game so that it starts to present chances to your team. On the mobile game, you don't get that same depth - so it's more about what you do off-the-pitch (and you've just said you want to play casually, so this is definitely the better option, as long as you don't mind living without the 3D match engine).