Mauser K98 - appears German, not jugoslav.
You have a WWW2 era Mauser K98. These were called Karabiner type 98. In my opinion this is one of the finest military rifles ever to be produced. It is certainly among the strongest actions and among the most accurate of it's day. I have some of these rifles and one in particular I will never sell or trade.
The markings on the side of the receiver ring on your rifle are unmistakably a stamp the pattern of which was generated under the third reich. Your rifle would have been made between 1938 and 1945. On top of the receiver ring might be a two-digit year stamp and near that stamp will be a factory code. You can easily decipher these factory codes with information available to find on the internet.
What little I can see of the wooden stock confirms that it is not a Yugoslav Mauser stock. You appear to have a German stock, probably the original stock. Maybe it is made of Beechwood. In the butt stock, it would appear the end of the sling (keeper) is wedged into the recess cut into the wood for that purpose. This is clearly from a K98 style sling.
The K98 was normally made in 7.92mm (8mm Mauser JS cartridge) and ammo is easily available on the surplus market, or from Remington. One of the finest military cartridges in the world.
You need to be aware of the fact that some who obtained these rifles at times had the chamber altered / reamed by a gunsmith (not that expensive to do) to use 30-06 brass loaded with an 8mm bullet. When you do that, you cant fire 8mm JS in the rifle. Also, this does not mean you can fire 30-06 cartridges in this rifle! Altering the chamber to an '06 case configuration gave a little bit more powder capacity in the case and it provided a common, easy to find, boxer-primed cartrdige casing for reloading their own ammo. They dont make factory produced 8mmx'06. They have to be made on the loading bench. Most of the K98 rifles were probably left intact in the standard 8mm Mauser JS cartridge. Dont go shoving cartridges in there and pulling the trigger until you have had the rifle looked over by someone who knows what they are doing with a Mauser rifle. Often we dont know where these rifles have been and what has been done to them. If the rifle checks out, you have yourself a nice rifle there. Quite valuable and if taken care of will last for generations.
In order to tell you more about the rifle, I would have to see more photos.
It looks like a nice rifle.