Chromebook owners may be eligible to receive free copies of Doom, Doom II, and The Elder Scrolls: Legends Fall of the Dark Brotherhood expansion. These are android ports of the original Doom and Doom II, not the updated 2016 game however they are still great games and will run on anything including your old Chromebook given it has Android support. The games normally cost 4.99 USD and 19.99 USD for The Elder Scrolls: Legends Fall of the Dark Brotherhood expansion, so you’re getting some good value. These perks are only available for a limited time and may not be available for all Chromebooks or regions.
You can check if your Chromebook is eligible: here