ERC does not become part of the 1040.

The employer is either supposed to report it on the 941, which allows them to hold back some of the funds they would have been depositing for Payroll taxes. Or, they file for the Payment when their own tax payment isn't enough to cover the amount they would be getting (credit vs advance). Or, now that it is over you file amended 941X to show they amount you are entitled to get refunded.

If you click the links I gave, you can read how to handle the offset of wages + employer tax used for the ERC and how to make the adjustment on the 1120S.

And you cannot use that same employee's wages for ERC and for WOC. That isn't allowed.

Did you click any of the links I gave, to read that reference materials? Here's another:

https://www.irs.gov/newsroom/employee-retention-credit-2020-vs-2021-comparison-chart

And:

https://wotc.com/erc-employee-retention-credit-cares-act/

"The CARES Act prohibits you from receiving the ERC for the SAME wages used for other credits:

• Wages for which you received a tax credit for paid sick and family leave under the Families First Coronavirus Response Act (Phase II);
• Any wages you counted as part of the credit for paid family and medical leave under section 45S of the Internal Revenue Code;
• Wages paid to certain related individuals; or
• Any employee for whom you were granted a Work Opportunity Tax Credit under section 51 of the Internal Revenue Code.

Under the CAA, 2021, this prohibition is also extended to wages affected by certain other credits including: the Research Activities Credit, Indian Employment Credit, Credit for Employer Differential Wage, and Empowerment Zone Employment Credit."

No double-dipping.