I'm not sure that the brands and models available here in the US are available in Lithuania, so it is best to do your own shopping.
Personally I recommend Seasonic and Corsair power supplies. Some Corsairs are made by Seasonic, but not all. There is a link "who makes your power supply" in that thread I posted above where you can find that stuff out.
You will use a ATX 12v/EPS 12v supply for your machine. Make sure it has an 8-pin connector for your processor.
As to size of supply (watts) I use this calculator: eXtreme Power Supply Calculator
Fill in ALL of your specs.
Most important is that last box: "Capacitor Aging". I always use 50%. That is because a power supply's output drops over time due to capacitor aging. It is common to reach 50% aging in 4 to 5 years. Heavy users can do half that. Buying a larger supply compensates for this known aging and extends the life of the supply.
If you are buying online look at the reviews. They will tell the tale.
This is a good supply to start with: Newegg.com - CORSAIR Enthusiast Series TX850 V2 850W ATX12V v2.31/ EPS12V v2.92 80 PLUS BRONZE Certified Active PFC High Performance Power Supply
Make note of the specs and compare them to anything else you are looking at.
I can assure you that more opinions and advice from other knowledgeable folks will follow. Everyone's needs and wants are different. It is all good.