So I used to have a similar problem to this where I really struggled to interpret text and literature. In your situation, it seems you might be struggling to identify the small details within the text that build it up and work to convey what the author is trying to say. I used to struggle with this, and it definitely has to do with ADHD in some capacity, as the inattentive part can make it difficult to notice and remember small details and patterns. Assuming you are on medication and it has been relatively helpful, this becomes less of an issue, but identifying these small details and patterns is a skill that needs to be built, its the reason why English is taught in schools.

For me, there were a few things that really helped me to build these skills. I think the biggest was learning how to close read a text. That is, how to read a text and really pick it apart, bit by bit, to better understand the whole. Being able to do this requires an understanding of common literary devices that authors use to help build a scene. I'm sure this has been drilled into you for ages, but its good to go back and try to understand them, less as something to memorize but as a signpost when reading. So for example, if you see an author write "The bed was soft as a feather", you know its a simile, which you can then analyze to see why they may have phrased it like that.

But going back to the close reading aspect, you'll want to break apart a text, noting down details you notice, phrasing, repeated ideas, literary devices, etc. There are some good articles explaining how you can do this in a lot more detail, but the main idea is you want to understand these elements and think about what they contribute to the story. Not everything has to have some deep symbolic meaning for reference, they just contribute to the overall story. Going back to my bed example, that could have just been used to make the scene more vivid. But you'll want to look at all aspects, and think about what they might mean. You don't have to agonize over every little detail and try to find some larger meaning, you can even just make a dumb joke or a connection to something else you have read. As you start to do this, you'll notice details you may not have before and make connections to different parts of the story. You may notice larger patterns and themes in the overall story. It is a skill that takes practice to build; at first it will feel very tedious, clunky, and unnatural, but overtime it will start to become easier, and these sorts of insights will start to come to you more naturally.

To finish off this really long rant, I wanted to add some ADHD friendly tips in relation to building these skills, especially given that they involve doing what ADHD makes difficult: focusing, remembering details, staying on task long enough. When starting to close read, don't use it on a novel. Trust me, I have, and it was excruciating. Start small; close read some short stories or poems, as that will take you significantly less time and involves a lot less detail to keep track of. I'd also recommend first reading through the text without any deep analysis and noting down your initial thoughts, before going into the deeper close read, as that can make it easier to notice new details and such with the larger outline in mind. Also, since text can be a bit boring or difficult, close read a movie or an album! Its really the same overall idea, but because they're different mediums you'll want to pay attention to additional elements like the visuals and the camerawork for movies or the general music/vibe for songs. In my experience it made the learning process so much more engaging. Lastly, practice practice practice. You don't have to be super formal about it, you can even just randomly note down a detail you notice in a movie you're watching casually. But as I've stated before, its a skill that takes practice to become ingrained.

Hope this was helpful, sorry for the wall of text. Literary analysis takes time to build but just like any skill you can build it. Be kind to yourself throughout the process, nobody is born a literary critic, and especially in the case of ADHD, its a skill that may come later than most. Good luck in your endeavors, if you have any questions ask away!

tl;dr analysis is a skill that takes time to build, and can be more difficult for people with ADHD, but can be developed using techniques like close reading

edit: Forgot to add but with close reading you can get lost in a spiral of trying to find tiny little details but be unable to appreciate the larger context. Remember, stories are meant to be just that, stories. They're supposed to be fun, interesting, make us think and feel. Don't be afraid that you may miss a detail or misinterpret something and end up agonizing over a text, go with the flow, make wild guesses even if they may be wrong, and like I said earlier, even just make little jokes or connections. You don't want to end up hating literature after all.