For players who purchased in regions like Russia or Poland, the game is often "region-locked" to those specific languages. While the official Steam settings may not always offer English as a toggle for these versions, you can manually install an English language pack using community-verified workarounds. How to Install the English Language Pack (PC)
Note: If the English option is grayed out or the game switches back to another language after launching, you likely have a region-locked version and need to proceed to Method 2. cod black ops 3 english language pack top
If you purchased the game legitimately on Steam and it is not a region-locked key, you might not need a language pack at all. You simply need to unlock the language via Steam. For players who purchased in regions like Russia