Look at where you found the link. If it came from a YouTube description, a random Discord server, or an unverified "free games" site, it is almost certainly unsafe.
Legitimate modern games are rarely distributed via random .rar files on third-party hosting sites. If you didn't download this from a verified storefront like Steam or GOG , it is likely a "repack" at best or a virus at worst. Black-Mesa-Definitive-Edition.rar
If you’re looking to play the real game, the best (and safest) way is to grab it on Steam, where it frequently goes on sale for a very low price. Look at where you found the link
If you didn't purchase the game through official channels, the safest move is to delete the file and run a full system scan with Malwarebytes or Windows Defender. If you didn't download this from a verified
Before doing anything, upload the file to VirusTotal to see if multiple antivirus engines flag it as malicious.