The status of the tax return you submitted will determine what you can do right now. If it is pending, you need to wait until the IRS Accepts or Rejects the return. If they reject the return, you can make your corrections including adding your wife's information then refile. If the IRS accepts your tax return, you will need to file an amendment.
Here are two TurboTax FAQs with information about tax return statuses and about amending your return. Because it is still early in the tax season, tax amendment instructions are not available yet. They will be available by late January or early February.
Do I Need to Amend my Tax Return:
How to Amend your Tax Return: