“I’ve always wanted to write a book” or some derivative comes my way about once a month and my advice remains the same: Do it. And forget advice—yes, forget advice.
There’s nothing wrong with seeking a community and people who can help you hone your craft. Even Stephen King needs editors and critiques. You will need feedback for the rest of your life, but you don’t have to rush in.
When I was first starting out, I was pretty much isolated from the writing community. That was a good thing. Once I joined, I met some amazing people, but if I hadn’t already been so committed, the other kind would have scared me off.
For reasons beyond me, a lot of veteran writers (other artists, too) treat it as their personal responsibility to decide who “should” be in their field. There’s this unspoken loathing for the newcomers who “think it’s easy” (though I’m guessing you already know better). But who cares how many typos there are? If you get to those magical words—The End—you’ve already surpassed most the world and deserve a round of applause.
Don’t waste your time with bridge trolls who attack newcomers. Find some helpful fairy who points you in the right direction. Or just become a hermit for a few years like I did.
Ultimately, you are an individual, original human being and no one else can tell the story in your heart. I’ve seen far too many people with genuine talent give up. This is a high investment, often low return business and it’s easy to get discouraged. So keep your chin up, work on that thick skin, and remember you are the only person in existence who can write that book.
But above all else, keep writing, keep writing, KEEP WRITING.