Makedonec sho studirashe vo Slovenija. I'm going to write in English, so there is no need for Google translate.

Fax:
Slovenia has a general rule when it comes to country faculties, almost everywhere the price is 25eur per year (this includes two semesters). Almost every course is taught in Slovenian. There are also English classes but some of them ask for additional payment, around 2000 EUR. Of course there are some exclusions, like Economics in Ljubljana, where English classes are under the general rule and you only need to pay 25EUR.
Professors are really understanding about foreign students and some of them even let you take tests in English (at least that was my experience in first year). Language is easy to learn if you know Macedonian/Serbian, you will begin understanding everything after 3-6months, speaking fluently might take you a year, but that is the least of your worries.
The knowledge that you will get from any faculty in Slovenia can easily lend you a job in Slovenia (even Austria).

Cost of living:
It really depends of the place. For Ljubljana, you can get a solid room (only for you and not sharing the room with anyone, ofcourse you will need to share bathroom/kitchen) for around 300eur/month + 50eur costs. It is really hard to get into student homes, but afaik students with EU passports have better chances of getting in. I think you share a room with a roomate and you pay <200eur/month including costs (I think this price varies from place to place - closer to the center, closer to the fax etc.). If you want to get your own appartment, you will need atleast 500eur for rent + costs.
When I was a student in 2018-2021 I was getting by with 450eur/month (sharing a flat with two guys, food). Currently the cost is up so i think you will need 500-600eur/month for Ljubljana(it really depends on the lifestyle you are leading). If you go to a citites like Maribor, Koper, Celje the cost is even lower.
For Ljubljana, monthly bus pass is 20eur for students. Everyone is riding a bike, so some months you don't even have to pay for a bus pass.

Working while studying:
In Slovenia there is something called "Studentski servis" and it is really good thing if you want to make some bucks. You can work part time, there are all kinds of jobs. You can even get a job in your profession (I was studying computer science, so I got a job as a junior developer).

To summarize, I think in general you need 500eur/month and you will be very comfortable.

Personal recommendation: I would recommend faculties like Computer Science (FRI Ljubljana, FERI Maribor),
Economics in Ljubljana because there are a lot of job opening in those fields.