To enter form SSA-1099:

1. Go to Search (upper right)
2. Type SSA-1099 and press enter
3. Click on the Jump to SSA-1099 link
4. Select Yes, let's work on Social Security benefits and click Continue.
5. Check the first box, Form SSA-1099.
6. Enter the amounts for yourself and your jointly-filing spouse. -- SSA-1099s for children and other dependents are not reported on your return. They should report it on their own return, but only if they're required to file a return for some other reason (this is uncommon).
7. Click Continue.