Since I was 12 or 13 years old I have wanted to write novels. I've always had stories pop into my head and I would imagine writing those stories. During long drives I work through story ideas as a form of daydreaming. It took me forty years to fulfill my desire to write a novel, but I finally self-published my first book in 2019. At this point in my life my primary goal is to keep writing. I don't think of it as a career or a full-time profession. I need to get a few more books finished to consider writing a career.
I think you must. A writer needs to be a good observer of human behavior, traits, speech and it's impossible not to include parts of yourself in your writing.
Pay attention in English class! Writing Asteroids was like a five year long writing course. My first editor tore it up and wrote out a list of basic punctuation as a cheat sheet. He must have been very frustrated. I must have edited and re-written the book six or seven times. I'm sure it's still not perfect, but as I wrote and learned, my writing improved.