ABOUT THIS GAME
https://store.steampowered.com/app/2280/DOOM__DOOM_II/

Keys available: 1
Activation: steam
🔑Region lock: global, region free

The purchase will get you a steam key! Activating the steam key:
1) You must download and install Steam http://steampowered.com/download/SteamInstall.msi (if not already installed).
2) Create a new account on Steam or go to an existing one.
3) Select "Activate via Steam ..." in the "My Games" section, and enter the key received after payment.
4) After activation, the game will appear in your list of games and you can install it.

Please don't forget to leave a feedback after successful activation of the game.

Please consider recording your attempt at activation of the key, it will protect you and us from unintentional misunderstanding in an unlikely event of invalid key. We recommend to use OBS.