Can’t understand the papers related to my field of research and having a hard time learning. Am I doomed to fail?

Hello, idk if this is the right place to ask but I need some advice on how to read and understand academic papers and learning in general.

First off, prefacing things, I’m a 4th undergraduate student in computer science. Diagnosed with adhd inattentive type last year currently unmediated if it matters. I stayed with my undergraduate PI and recently accepted into the Electrical Engineering program with emphasis on hardware based security and cryptography.

My PI is quite new, she worked in the industry for few years before moving into academia and she’s quite ambitious and motivated. She currently have 1 actual PhD student working under her.

This semester she started to make us read papers published in our related field, asked us to go over them and present them in weekly meetings going over the papers in details such as motivation, idea, implementations, results and most importantly how we can learn from them.

I’m currently struggling to read the papers she assigned to me, and present them coherently. I can tell she was unsatisfied with my presentations. But deep down my struggling to read and understand the paper, grasping key concepts mentioned in them. Seems like I’m reading normally, understanding what each individual word means but failed to understand them when I put them together. I’m basically going blind into this field, learning them from ground zero and it’s been a struggle.

I feel deeply inadequate compare to the other PhD student in my lab group cuz he seems to truly understand the concepts and what the paper is saying and even offering critique to them.

Am I just not enough for getting a PhD ? Is this journey ending before it even begins? Any tips or just general advice on how to be better? I understand that the most valuable thing for a PhD is the ability to learn and seems like I don’t have that at all.