Alright I read the initial first three chapters and I can say that you have a few things we can work on.
The Negatives:
You throw the reader into this world without any sort of context to it and it just comes off as you are supposed to know these words and terms with out any sort of in world reference.
Also the main character doesn't even have a moniker or name to go by, at least that I have seen. We are just thrown into this person's POV.
This character doesn't really have any ground to stand either, I couldn't help but feel detached from him as he rambles on about random people or things that I as a reader don't feel much attachment to.
The lack of description isn't helping, as I can't imagine what our main character looks like, only that the main character has shoulder length brown hair and that he is attractive to both men and women and the only person that seems to get descriptors happens to be the main character's love interest and his older brother.
There also a myriad of names thrown around with one off lines that don't real help me draw me into the story.
The action feel very static and leaves much to be desired as many of the actions are told to us as readers rather than shown.
The story's tone bounces all over the place, I can't tell if this is supposed to be a slum world nightmare or an edgy, humorous, Borderlands-esque world.
The Positives:
The world has some interesting lore that has already been introduced albeit in a showy way and leaves more to want to be learn, and you don't info dump the lore of this world in the first few paragraphs which leaves us time to discover these things later throughout the story.
The grammar is on point besides one or two minor errors and has consistent structure and doesn't run on forever.
Your presentation of some aspects of the story leave me wanting more to be discovered about the main character's world and how it came to be this way.
There is a single significant attachment the main character has that I can attach myself too which is their terminally ill brother that attempt to put a brave facade in front of which gives the main character some depth.
And finally you seem to be driving the story in a coherent direction and not just letting it stagnate via slice of life sections.
Personal Issues:
So I am not a fan of system esque stories, I'll be frank with you there.
Also I have an issue with the apparent job system that is in the story. You mention a warrior and mage class as classical LitRPG classes, but also have things like Torturers and Cancer Patients as classes. Which leaves me wondering if the system gives you a class bases on your state of being or your profession.
Also I am not a big fan of references in works, as you may know I find it dates your work and alienates part of your audience.
In Summary:
Despite the various issues with the story there are strong aspects that I enjoy, I can only hope my advice helps and you continue with your writing career.