If the text in the launcher window is red, it's likely because the launcher is looking for a Steam installation in a default location like C:\Program Files (x86)\steam and cannot find it.

Now, let’s answer the core question:

To ensure maximum security and stability, the best approach is to purchase a legitimate license directly from official platforms like the official Sniper Elite 4 Steam Page . Purchasing official releases protects your hardware, provides cloud saves, and gives you instant access to verified, stable multiplayer servers without complex workarounds.

If you trust the source origin of your download, you can select "Restore". (Note: Doing so is at your own risk).