After you've been assigned Medications in your surrogacy journey, you can use the "Medication" tab to view your daily Medication. When you've completed your daily Medication, press the "I've completed this/these medication(s)" button to mark your daily Medications as complete. After marking a day's Medication as complete, you are also able to upload related pictures.
You can also keep track of them in your "Calendar" page. You can also tap on each Medication to view its details, mark a Medication as complete or upload photos for completed Medications.