Anyone can write. It's actually rather easy to just stick a bunch of words together and call it a story. But not everyone can write well, right away. It takes time, effort, and dedication to hone your craft from a collection of words into a masterpiece of language.
Learning how to write well is a depressing notion. You have to learn grammar and spelling and structure and scene and dialogue and character and plot and showing vs. telling and exposition and any number of other things that you never notice when you read because the author is a master at hiding how much effort it actually takes.
Writing is time-consuming and frustrating because there are times when you'll make it halfway through a novel only to realize you have to start over because what you've written doesn't mesh with what you want to write. It's heartbreaking and terrifying because the first time you finish a story--of whatever length--and hand it over to a friend or a parent or a sibling to read you'll be forced to watch their brow furrow as they mouth the words on the page in an attempt to make sense of it. You'll want to quit and never write again. You'll want to hide your work and never show it to anyone. You'll want to tell people that they're just not sophisticated enough to understand your vision.
Don't do any of that.
Because as hard and frustrating and heartbreaking as writing can be, it can also be the most liberating and beautiful part of your life.
Writing, like any art, is a reflection of the author's soul. It doesn't matter if you write poetry or prose, fiction or non-fiction, literary or genre, a little bit of yourself will always be contained in those pages whether it's in the setting or a specific character or the voice used to tell the story. Because of that, a budding writer needs to feel safe when expressing themselves. You need support and encouragement to continue on doing what seems impossible.
Some people have that support through friends or family or the local writer's club that meets at the library twice a week. If you're one of those people, that's fantastic. Draw from that support, lean on them and learn from them and always be teachable. If you can't be taught you can't learn, and if you can't learn you can't improve.
If, however, you don't have that support, then I am hoping to offer you at least a modicum of help/support/commiseration by sharing with you many of the things I wish I had known when I first started in the trade. However, please keep in mind that, technically, I am still a novice as I have yet to publish anything substantial. All I can offer you are ten years of trial and error as I slowly inch my way toward the starting line; because getting published is only the beginning...
Happy Writing!