Yes. No Serbian law forbids individuals or companies from using a VPN.

The main area where Serbia restricts websites is betting. The Law on Games of Chance reserves gambling for licensed organisers, and since October 2020 internet operators have blocked sites on a list kept by the Games of Chance Administration at the Ministry of Finance. Some people reach such sites through a VPN or a proxy, but a betting site without a Serbian licence stays unlicensed whatever the route, so it is worth being careful.

A VPN does two things: it encrypts the connection between your device and the VPN, and it shows websites an IP address from the location you choose. Laws, account rules and the terms of the sites you visit stay the same. The Browsec blog covers how a VPN works in more detail.