You should be with this specific file. A file named DOWNLOAD FILE – HALF-LIFE: OPPOSING FORCE.RAR —especially with the broken character encoding ( – )—is a classic hallmark of malware or a "browser hijacker" scam .
: Do not open this .rar file. If you have already downloaded it, delete it immediately and run a full system scan with a reputable antivirus like Malwarebytes or Windows Defender . DOWNLOAD FILE – HALF-LIFE: OPPOSING FORCE.RAR
If you want to play the game safely, I recommend using these official or highly-trusted sources: You should be with this specific file