The Steps card on the Fitbit app dashboard will not appear unless you have a Fitbit device linked to your Fitbit account, or you have MobileTrack enabled on your phone. You don't have to wear the Fitbit device, or even turn it on, you just have to have one linked to your account.
If you don't have a Fitbit device, you can set up MobileTrack. For instructions on setting up MobileTrack to work with Health App to Fitbit Sync, please see this page of our FAQ.