In the book Outliers Malcolm Gladwell says that 10,000 hours of practice will make you an expert. Okay, this is a major paraphrase and simplification, but it works for our purposes now. I'll get into that book another time. Spoiler: it's amazing.
In the writer's world, people have equated 10,000 hours of practice into roughly 1 million published words. Does that mean that you need to write a million words before you can make a living at writing? No, it means that the best of the best of the best in the writing community have published a million "quality" words. Think about all the really famous and amazing authors you know out there: George R.R. Martin, Brandon Sanderson, Lee Child, J.K. Rowling, all experts in their field, top of the pyramid, and a million words easily. In Brandon's case, a million words almost yearly, but we can discuss BrandBot's antics another time.
Today I wanted to drive home the point that 10,000 hours, or 1 million words is an achievable goal. You can start making money off your writing far earlier than that, it's just that you might not become an "expert" in the field for a while after that.
It also drives home the notion that you need to write, edit, and then publish your work. Each phase requires different skills, and each phase needs to be practiced on it's own.
One of the big mistakes I made earlier on in my career was not finishing things I started. Sure, I got it through my skull that all my writing at the beginning was crap, at least I got that far, but I didn't follow through by editing my first four novels. I thought I needed to practice drafting first, then move on to the next phase. While I did get better with each attempt, you don't truly learn story structure until you edit story structure, and you don't learn to critique unless you practice. Thus, joining my first critique group was one of the smartest decisions I ever made, and I should have done it sooner.
Yesterday, I suggested joining a critique group, but I didn't specify which ones, because at that stage it didn't matter. There are a lot of meetup groups out there where you'll see 100+ members listed on the roster, and those are great for starting out. Most times, those groups are fairly transient, and they involve people reading aloud their work for 5-10 minutes then getting a little bit of feedback from the audience. This is a good start, but it's not enough to truly learn.
In this phase, you've written some short stories, you've edited them, even gotten some feedback and hopefully improved. Now, it's time to buckle down and start working toward your first book, and also join your first real writing group.
Not to bash the other writing groups, they're good, but in my experience, they're more social gatherings. The transient nature of the groups means it's difficult to develop lasting friendships and working partnerships with other serious writers, and the method, that of reading aloud, means people only hear your work once, briefly, before giving feedback. Editors don't do it this way, they sit down with your manuscript with a red pen, (or Word's equivalent) and mark the hell out of your story. You need a critique group that will do the same.
Look for a closed Meetup group of less than 10 people. I've found around 6 to be optimum. You need to apply to join these groups, usually through a submission process. These are usually serious people looking to publish, and working hard to get there.
Alternatively, start a group once you've met others via one of the other groups. Look for like-minded people who are serious about their craft, are as well-read as you, preferably in the same genre as you, but that' not mandatory. I'm in a group with all romance writers, and I write epic fantasy.
The group should meet every other week, with submissions due a week prior. Expect to invest some serious time into the group. Spend a couple hours per manuscript at first. Yes, that means you might end up spending 12-16 hours a week on your critique group. It's time well-invested. You get free editing from the process, and quality editors are expensive. Besides, you don't need a professional editor at this stage.
Each time you critique someone else, you will get incrementally better at seeing the same flaws in your writing. Don't rush it, you are learning, but you should see a marked improvement in your writing after six months. Write new stories as well, or begin work on your first novel, but I'd still recommend stories at first, as they can be re-written after the critique and resubmitted for immediate feedback.
You're also doing this while still reading a lot, writing every day, and adding critiquing to your tool belt. You're slowly growing with each story and building a foundation to last you a career.