Board Game Arena

I was wondering if there will be a tutorial for this game. I don't own it, but I'm curious about it, and since it's a relatively long game I don't want to ruin a game for other people by just pretending to know how to play it for more than an hour

There is this thing:
https://boardgamearena.com/archive/repl ... ;&tutorial

You can also play it in solo mode.
Which is admittedly different from competitive play (in that you are more focused on the global goals than getting points), but it will give you a basic understanding of the game.

Solo mode works really well to learn the mechanics. As with all solo games, if you set it to turn based you can really take your time.