@rotblau
Welcome to the expat.com forum and good luck with your potential move to Bulgaria!
The official minimum salary has recently been increased, so it's just over 400 euros per month.
So your salary of about 1,250 euros is substantially more.
You are correct that Sofia is the most expensive city here, but, even so, for a single person, it should be possible to live on this. However, I doubt that it would be easy, and your life here would tend more towards "frugal", rather than "comfortable".
For example, I'd guess you'll have some taxes and social security deductions... maybe 250 euros, leaving 1,000 in your pocket. The cheapest studio apartment might be under 400 euros, plus you'll need another 100 or so for utilities. That would leave you just 500 euros to live for a month, so I suspect you'd be better off trying to rent a room in a shared house/flat instead (hopefully 250 ish, maybe with some of your new colleagues).
The upside is that Bulgaria is in the EU, and Sofia is a thriving capital city. So if you want to get into the EU (5 years of residence to permanent residence) then you might be willing to accept some short-term hardship. If it's a successful company, there might be potential for promotions or bonuses or pay rises later. Tech is a good sector, so there might be better-paying opportunities with other Sofia companies, once you've gained some experience. When you have your PR, you might find it's relatively easy to move elsewhere in the EU for better-paying jobs (Bulgaria has the lowest salaries in the EU).
I don't think Game Presenters are the highest rung on the tech ladder, but you gotta start somewhere, right? :-) If you're young and you've got some languages skills (and don't eat much) it might be good. These tech companies typically have a very young workforce, so it can be quite a fun environment and relatively easy to make friends. I'm very biased, as I took a tech job when I was 18, even though they were paying me peanuts. It was a struggle to live on it, but it was a great work environment and it got me a couple of years experience which I was able to leverage later. If you're much older, or you've got lots of other offers, or you have a very comfortable life/career in Turkey already, or you have no interest in the EU, then it's a different calculation.