Sites like Instant Gaming or G2A often sell Steam keys for the Apex edition at discounted rates. System Requirements for Arma 3 Apex
Arma 3 and its Apex expansion are not officially available as a free download for the full version. The game is a and typically requires a purchase. download-arma-3-apex-pc-game-full-version-free
Before downloading, ensure your PC meets the minimum requirements : Windows 10 (64-bit) Processor: Intel Core quad-core or AMD Athlon quad-core Memory: 8 GB RAM Sites like Instant Gaming or G2A often sell