In Excel 2016 you wish to insert a new row between the current row 5 and row 6. You should Select one:

a. click on row header of row 6 and click "Insert in the Cells section of the Home tab.

b. click on row header of row 5 and click "Insert in the Cells section of the Home tab.

c. click in any cell on row 6 and hit the Insert key on the keyboard

d. click on any cell in row 5 and hit the Insert key on the keyboard