If you see the options for "Spouse's personal information" and "Additional information about Spouse" under "My Info" in the left side menu, then you are only preparing your own return. You would enter your spouse's information on those pages.
If you want to prepare your return together with your spouse, then you would need to start your return over to choose that option.
To start a new return, select “Start a New Return” from under “My Returns” in the top left corner. Once you have started your new return, you can select “View All Returns” from under “My Accounts & Returns”. Then delete the unwanted return by clicking the small Trash Can next to it or “Delete” under the return’s name.