There is no feature available to permanently delete an Eternal Return account.
Instead, if you want to reset your account's progress, you can contact the game's developer, Nimble Neuron, and they will be able to unlink the game from your Steam account. You can reach them through this page.
Once the account is unlinked, you'll be able to create a brand-new one by launching the game from Steam as normal.
Please note that even after the account is unlinked, the game will still be visible in your Steam Library.
Should you want to remove the game from your Steam Library, follow these steps:
- Open up Eternal Return’s page in your Steam Library
- Click on the Cogwheel icon
- Click on “Manage”
- Click on “Remove from account”