Reference in a formula

Hello community,

I need to get the result of a cell (20) using a formula that references a column and a row. I have tried this way:

D7 -> 20
D10 -> ="Sales!D"&ROW(7)    //Sales is the sheet name and D the column

but the result I get back is the formula in text:
Sales!D7

I need the row to be variable but the sheet and column will be fixed.

What would be the correct formula?
Thank you very much