No, you can't write really abstract fiction (well you can write it but nobody will read it).
As far as writing goes, you have a decent place to start.
From my experience, writing is a mechanical skill that is all about practice and reading and not particularly valuable in itself. That's why there are so many writers out there. Anyone can do it.
That's actually not a bad thing, because anyone can read too and unlike the rarefied and deconstructed to death visual "arts", literature is still a middle class art form, accessible to everyone (not just people who can pay $300,000 to mount a partly destroyed urinal on their wall). The universality of access is what gives great writers a status that visual "artists" will never have.
Writing, in itself, is cheap, and quite frankly there is so much of it out there that the hardest thing to do is to be noticed. What a lot of people do not realize is that the most important part isn't the writing; it's the storytelling.
Telling a story is the oldest human art form and still the most powerful and intimate. A good book goes with the reader to the bath tub or the bedside table and lives in their house for decades like a family member. It gets dog-eared and the spine broken and wine stained, and no other form of art can match it for being loved. Novels are the old, torn up teddy bears of human creative expression.
So the important thing is to have a story.
You observe people. That's very good. Observation, not deep thinking, is the most important skill for the novelist. Seeing how people do things, listening to how they speak, being sensitive to how they express things on multiple levels simultaneously, and then working very very hard with a lot of discipline to boil that down to the absolute most concise description is a lot of what makes a great novel. The thing is, you need a story. Not just some story that you think about for a minute and go "You know, that could be a book...". You need a story that sits in your mind and grows and grows and won't go away and gets so big that is must be written down or you are going to explode.
To get a story like that, you really need life experience. It doesn't have to be adventurous like Hemingway, but what he did that was so smart was constantly expose himself to new experiences and new people. He absorbed life in all the time and tried to find the most "real" experiences he could, and he knew that suffering and pain is part of life and sometimes (no, always) gives us the best stories in the end.
Staying in your room being comfortable is ok, and you might even come up with a couple stories, but I doubt you will develop a STORY that way. Since everyone writes and everyone has a couple (lowercase) stories nowadays, it isn't a good way to be noticed.
As far as abstraction: Novels are immune to abstract expression. That is the power of the novel as a form of art.
You can't actually write a modernist or postmodernist novel. Not really. You can go James Joyce and get impressionistic, but that's about as far as the form can stretch. Since people have already read Joyce (or pretend they did), nobody wants that anymore because it isn't very nice to read, so there's no demand for it. If you go full on "modern art", you end up with word soup, which, by definition, is NOT a novel and won't be called one nor read by anyone. The reason for this is because language is our medium and language is a utilitarian thing with exact meanings for words which must always be placed together in certain ways. If you get too experimental, you are, by definition, no longer telling a story. If you aren't telling a story, it's not a novel.
You can have totally incomprehensible "poetry", but then again, poetry is only published out of pity by non profit organizations who think it's sad that we don't have more poets (despite the fact that real poets make a perfectly decent living writing songs for singers in Nashville and elsewhere).
As far as total deconstruction: unlike visual arts, true deconstruction of a novel destroys the medium itself (language), which leaves nothing. Not even a blank canvass, just no "canvass" at all. So, because telling a story is the goal of fiction writing, you can't get too abstract or you lose the ability to communicate with your reader.
The magic of writing is the intimate connection between the reader and the writer, and the way the story comes to life in the reader's head like internal performance art. It allows them to experience things they never could have otherwise, and makes them think of things they never would have thought of, and (if done properly) it moves them in ways they didn't expect. You don't want to do anything that will interfere with that connection (like writing in an outline form or trying to be abstract). Likewise, you don't add much value to the reader if everything you describe is something they easily could have thought of themselves or have experienced plenty of times.
Great storytellers get out into the world and find the stories. There are so many stories out there you will never find the end of them. If you think you are such a font of genius that no story someone other than yourself tells you or you experience with someone else is as good as what you can just come up with in your room, you will never be very interesting. Have the humility to not only observe people but also listen to them. Meet them, find them.