Your English is fine, it's just a matter of terms.

If a game is region restricted, then when you buy it in a "cheap" region, it can't be activated in an "expensive" region. For example, I buy the game in Russia, and someone in Germany can't activate my copy, like Metro: Last Light. This is generally a bad thing if you get it wrong, so region restrictions must be included with giveaways.

If a game is purchase restricted, then there are some places where you cannot even buy it. But anyone who has a copy can give it to you, and you can activate it anyway. This makes purchase restrictions even stupider than region restrictions. It also means that it doesn't matter for giveaways, though. That's why I had to point it out, otherwise some people might think there's a problem with the giveaway.

According to SteamDB, you live in China, Hong Kong, Japan, Taiwan or one of the Koreas, where this game can't be bought (and therefore the store page is unavailable), but there are no restrictions on where it can be activated.