Even though I’m as of yet unpublished, I’ve read a few “how-to” books on writing.
The number one rule I’ve found is to finish what you start.
I took a community college writing class and the class project was to write a short story, 6K to 8K words. Over the course of a couple of months, I was able to finish the project. It was awful, but it was complete. It also gave me the confidence that I could actually finish a project if I put my mind to it.
I highly recommend finishing what you start. Don’t give up, even if you think it’s terrible.