The biggest hurdle I faced when it came to writing was strategy. I had taken some writing classes and read several books and I tried to follow the advice they gave. It didn't work. I kept getting stuck.
My biggest problem is that I'm a perfectionist. I would write a chapter, then want to go back and write and rewrite until it was the finished product. Of course, by then, all forward momentum was lost. I started four or five novels this way that ended at chapter three or four.
The other problem was that I had been taught that you are supposed to outline your stories. I would come up with outlines, but they never seemed to work for me. I figured that I must be a failure at writing and gave up for a while.
My daughter discovered an event called NaNoWriMo, National Novel Writing Month. Three years ago, we both decided to do this together, you know, so that we would have someone to commiserated with when we got frustrated. The main objective of NaNoWriMo is to write a 50,000 novel in 30 days (November, usually).
When I got started, the perfectionist in me said, "Let's go back and fix what we just wrote." In which I would have to answer back, "Quiet, we don't have time for that!" (Yes, I do have conversations with myself).
It turned out, in order to stay on schedule, that I had to turn off the perfectionist voice (it whined a lot, but eventually settled down to a whimper). This led me to find out that I am what they call a 'discovery writer'. Most of the time, I have no idea what is going to happen in the next chapter until I write it. This makes it exciting for me and can lead into unpredictable situations. There are also plenty of pitfalls, too, which I will maybe go into another time.
My main point is, though, that you, the aspiring author, needs to find a method that works for you. You might be an 'outliner' or you may be a 'discoverer' or somewhere in between. What you need to do is to try different writing approaches and see what works best for you. Just because some famous writer uses a certain approach doesn't mean it will work for you. We're all different. So, do some research and find out how different writers approach their art and then try their method for a bit. If that doesn't work, try something else until you find something that works.