How to copy a cell ontent into next available blank cell in sheet2?

I have 2 worksheets, let's call them "Sheet1" and "sheet2".

Sheet 1 has 2 columns (A, and B)

Ie. "Sheet1:"

Col A, Col B

Red
Green Yes
Blue
Yellow
Orange Yes

For each entry in Column "B" that has a "Yes" value, I need to copy the color value in column "A" into the next available empty cell in "Sheet2" in column A.

"Sheet2"

Col A, Col B

Red 3
Blue 5
Yellow 6


Final Result:

Col A, Col B


Red 3
Blue 5
Yellow 6
Green
Orange

Can someone assist in how to do this particular challenge? For Sheet2, I think I'll need a function to determine the first available blank cell in column A.

Thanks