In order to delete your account you’ll have to contact Steam Customer Center.
However, before proceeding further in deleting your Steam account,
please check the below details.
1) Once after deleting your steam account you’ll not be able to retrieve it again.
2) After you delete your account, you will not be receiving any refund
for the game you’d purchased.
3) After deleting your account, you will not be able to utilize the remaining amount
in your Steam Wallet.
4) You can not use any CD key that you’ve used in your deleted account.
5) Your profile will be deleted.
6) Posts from the Steam Community where your account was active will not be deleted.
7) You can not create the same login ID after leaving the account.
If you have verified all of the above details,
please proceed to the Steam Customer Center and follow the process to delete your account.