Kinda depends on what you think of as high level.

Now, only some of what I’m going to say is first person, because I’ve never “drawn” professionally, and that’s part of what you’re asking. So be aware of that.

But, if you want to reach the point where you could realistically be a professional comic artist, expect to put in some work. Maybe years worth. Even the artists that get their first job early tend to have years of practice in, working with perspective, the human form, and general use of the tools of the trade.

Like, you don’t necessarily need art school to achieve technical proficiency, but you do need practice that’s going to be the equivalent in time. If that’s you doing the work independently as a teen and young adult in your time, great.

But that’s just technical proficiency. All the comic artists I’ve ever heard describe their job, it’s not just being good, it’s being fast, because even the indies that publish their own stuff can’t just have no schedule because things have to ship and be on shelves at a reasonable degree of accuracy, or not only do the shops have trouble with that, readers give up and forget about it.

All the stuff with layout in panels, formatting, etc, you can learn as you go, once you’ve got the fundamentals down, but don’t expect a ton of interest at first. Doesn’t matter how good the drawings are if they don’t fit the page and tell the story. If that side of things is sloppy, making money at comics is harder.

I actually know one artist that went from high school, to art school, and into pencil work by the time he was 21 at marvel. Not naming him, but he had been working on his skills as far back as elementary school, and had gotten serious about it before high school, and that’s how he got a job of any kind that quick.

Thing is, comics are harder than they look. A lot of them, you aren’t doing super realistic stuff. But you have to convey movement and dynamics in a scene. You have to do that in a limited space, and clearly enough for an inker to have something to work with, then the colorist if it’s a color comic. Just sitting down and doing a realistic sketch of someone might take an hour to get nice enough to hang on the wall, but doing a page of a comic can take just as long or longer, depending on what’s going on.

The simpler the comic is, the less work you have to do, but you still gotta do enough to tell the story.

So don’t expect to get good at all of that fast. Expect it to take at least as long s an associate’s degree if you’re already into art. Longer if you’re starting from scratch