How do I actually amend a previous year's return? The general answer says to click "Tax home" and then "your returns & tax docs" but neither of those are visible.

The only way to get to my tax docs is to click "Intuit account" and even then, there's no button to "start amendment" as the general answer claims. 
I need to add a K-1 to a previous year. Any help would be appreciated. Thank you!