There's no tutorial, because it's a creative medium. Try shit out and see what you enjoy. If you're out of ideas, try recreating something else you've seen as closely as you can, to practice your craft. The mistakes you make along the journey will generate ideas for you.
We don't tell people to just throw some vegetables in a pan and expect ratatouille; or to pick up a trumpet and presto, they play jazz.
Plenty of other people gave links to tutorials, and those are all fine. I wanted to emphasize that this is a skill that takes time, effort, a good amount of practice, and play to get comfortable with.
I think too many people are scared of learning a skill, and want tutorials to guide them through the process. There was a post a week ago about an app trying to teach people how to cook by asking them to find a picture of a "scrambled egg" in a line-up. Obviously useless, and that doesn't get people any closer to what actually needs to happen -- just pick up a pan and try. No, you won't get it right the first time. Nobody does. That's what the practice is for.
Start by actually starting.
Who claimed that, or anything similar?
Rudimentary coding skills, a text editor, know a little math. That will take you far.
I guess the comment you're replying to is making the point that the tools can be very, very simple and OP probably already knows enough. The bit they are missing is "just start trying stuff"