You can fill in both sections, if you have something for both. Or only the bottom part if you have an expense that you only use for your work space and not for personal use in the rest of the house.
If you enter an expense in "Expenses which you incurred for the entire home", then you would put in the entire amount for the whole house. The program will calculate what part can be deducted based on the amount of the home you use for work. So you would enter $2000 and then TurboTax will reduce it to $200.
