If the IRS accepts your return, wait for it to be fully processed. Then you can amend to add the retirement income.
See this TurboTax support FAQ for amending a tax return - https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-change-correct-return-a...
Go to Federal> Wages & Income>>Retirement Plans and Social Security (SSA1099 and 1099RRB) to enter your SSA1099.
To enter your retirement income, Go to Federal> Wages and Income>Retirement Plans and Social Security>IRA 401 k) Pension Plan Withdrawals to enter your 1099R.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
