Writing is a skill that takes many years to learn and requires a lot of study and work. I would recommend that you read a few books on screenwriting. Story by Robert McKee is a great book that covers the basics of storytelling for the screen. There are also many (professional) scripts available online and reading these will greatly help develop a writer's skill. In terms of this story, the best approach is to to find a specific goal for the protagonist and to build the story around the protagonist as he pursues his goal. 

The Script works very well on a craft and a structural level. Currently, the ending and medical explanation are a bit unclear but other than that the story needs more heart and that comes from having empathy with the protagonist rather than condemning him. To do this the short should dig into the protagonist's internal world and see him more as a tragic hero examining why he suffers this addiction rather than condemn him for being unable to overcome it.

The current script has a good premise and a decent story which is executed very well on the page. But it does essentially need more. More plot, more character and more stroy. The way to achieve that is to deepen the characters by giving them more of a backstory and examining the internal arcs.

It’s a very well-executed short. The only issue is that the ending does not pack quite as much punch as it could, so I would look at developing that a bit more, as well as addressing the initial dialogue between Marshal and Quinton

The prose and dialogue were written very well and the script flowed smoothly, made sense, and had some nice emotional moments. But because the underlying storytelling structure was not effective those emotional moments did not fully hit home. Adding a physical and achievable goal for the protagonist would give him something to pursue and obstacles to overcome while this relationship drama plays out. This would make the protagonist active and give the story both the legs and the structure it needs.

The Script read very well and the world was wonderfully interesting and immersive, while the opening few pages were one of the best introductions to a story I have read in a very long time. However, the setup of the story does need much more consideration in terms of the protagonist and their goals, who is driving the story, and to what end. It does also need some fresh ideas to add to this scenario – changing the system is one but might not be quite enough. Does Levi have an alternative system that could be hinted at? Finally, I do recommend this book about the trickster as it is all about crossing boundaries, breaking rules, and changing systems and societies and this is a role that both Levi and Rachel play to some degree or other and essentially, what the story is about.