How do i enter distribution of retained earnings in form 1120s

To enter distribution of retained earnings in form 1120S, please follow these steps:

1. In the Find box at the top right of your screen, type distributions to shareholders.  Click on the Jump to Distributions to shareholders link at the top of the list.
2. On the 2018 Distributions to Shareholders screen, mark the radio button Yes, the corporation made distributions to shareholders in 2018 and click Continue.
   

[You can also reach this section by clicking Business Info > Shareholder Information. Continue to the screen, 2018 Distributions to Shareholders.]

I thought that there is not such thing as Retained Earnings for an S corp. No?

An S-Corp can have retained earnings, however tax on all the profit must be paid by the shareholders for the year the profit was earned. 

S-Corp retained earnings