I'm a natural pantser. I struggled to finish stuff. I found learning about story structure and that helped a lot. And the more I wrote, the more I drifted towards outliner. I get pretty detailed now, but there's always room to pants things out.
The outline isn't written in stone. It's constantly evolving.
With short stories, I usually pants everything. But the key thing I have to know before I can write is what the character wants. Without that, it's impossible for me to finish or get much of a start, because that's what drives the story forward. Without it, it's just a vignette about not much.
Here's something that might help. Check out the sample section in this book. Yes, it's a screenwriting book, but it applies to writing novels, too. Scroll down to the part about the Central Question and the Three Parts to the Central Question. This will help you figure out what the character wants.
https://www.amazon.com/Story-Can-Beat-Your-Screenplay-ebook/dp/B00696HIYA