Experience is the best teacher. Some casinos has free trial for their games so that players can try and learn the mechanics of a certain game. Video tutorials are good references, but trying the game by yourself will give you more experience and knowledge about a certain game.
Yep, no matter how many tutorials you watched on how to play a casino game and how to place bet on them it won't take the place of the real thing and when you are doing it yourself, as long as there are free tests and demos for new players there won't be any need to make it look complicated while it's actually not, it's something like other usual games that you play on your phone maybe with some minor differences, most people that want to gamble will try out that game a few times before gambling real money anyway and that really should be more than enough for them learn and know whether they're good at it and want to gamble on it or not.
I started my gambling journey with slots in physical casinos. But since I can't go to physical casinos more often, I found out online dice websites, which is very comfortable to use anywhere you go, started with faucets from the site itself. And the rest is history. And during this crisis, online casinos have real advantage over physical ones. And maybe, this is the reason why you can see new online casinos being launched everyday as this industry is really booming these days.