.....the main problem is the story....
This is the discussion that you
should be having. What problems are you having with story? Also, what are you good at, so far. You are only 16, so give yourself some time, you have many years ahead to learn things, many new things that you will experience.
However, I do understand the tremendous synergy that can be attained by collaborative effort. One of my favorite old-school directors, Frank Capra, had a frequent collaborator in Robert Riskin. They would lock themselves into a hotel room in Southern California for a few weeks and hammer out a script. Capra had the basic story and a coupe of high points, and Riskin would flesh it all out, write the dialog and punch holes in the plot.
Just as a side-bar.... Capra was a prolific director during the "silent" film era. Because he was trained as an engineer, Capra was one of the first directors to fully understand and embrace sound-for-picture during the transitional period in the late 1920s and early 1930s. Capra set the framework for the modern Rom-Com with his Oscar-winning "It Happened One Night," which was also one of the earliest "road" movies. His film "Mr. Deeds Goes To Town" established the odd-ball hero. "Mr. Smith Goes To Washington" was so politically controversial that members of Congress actually tried to prevent the films release. In "Meet John Doe"
all of the characters are, at least initially, motivated entirely by self interest. And, of course, there is his Christmas classic "It's A Wonderful Life," which, BTW, won an Oscar for Special Effects with a new way of creating snow for film sets. A much more important director than he is given credit for.
Anyway, enough with the history lesson. Present us with a few of your scripts and we will rip them to shreds. Most folks here will be gently brutal about it. My audio post peers and I regularly harshly criticize each others work, even after years of experience. It takes a while, but you learn the difference between real constructive criticism and mean spirited snarky-ness; you'll mostly get the former here on IndieTalk.