Steam doesn't give away any free games as significantly as I know. You may expect a huge discounts every now and then but nothing to free unless it is free to play video games. t's very difficult to sink into the steam firewall as they hire hackers to safe guard it. Thus if you are a black hat, it might be a tough obstacle
I received a free copy of Company of Heroes 2 last yr not via Steam but through ‘Scdkey'. Scdkey.com is definitely like Steam program, a intermediary who markets games and software. They will have good discounts just like Steam sales every now and then and sometimes a free giveaway
steam keys that you can redeem on Steam.