I?m having trouble figuring out where to enter my s-corp distribution. Here is a simplified example of what I?m confused about.

Form 1120s:
Gross Sales = $50,000 entered on line 1c & 6
Salaries(w2)= $10,000 entered on line 8
Other deductions = $10,000 entered on line 19
These numbers make line 20 = $30,000
These numbers make line 21 = $20,000

I would like to take the line 21 - $20,000 as a tax free distribution. Where do I enter it on line 1120s and is it carried over to form k-1 ?