Here's a more detailed breakdown:
Access Steam Support: Go to steamhost.cn/help_steampowered_com and log in.

Find the Purchase: Navigate to your purchase history and locate the game you wish to refund.

Initiate Refund Request: Select the game and click on the "I want a refund" option, then choose "I'd like to request a refund".

Complete the Form: Fill out the refund form, providing a reason for your request in the notes section.

Submit and Wait: Submit the refund request and wait for Steam to process it.

you can do it here on steam app to

Refunds are generally granted for purchases made within the last 14 days and You must have played the game for less than 2 hours

https://steamhost.cn/account/history/

Find the game and select I would like a refund

Here are the steps to request a refund (with pictures) https://steamhost.cn/help_steampowered_com/en/faqs/view/784C-923B-A4A1-C825


And here is a link to Steam purchase history
https://steamhost.cn/help_steampowered_com/en/wizard/HelpWithPurchase