How do integrate InfoPath, SharePoint Designer 2013, and SharePoint 2013 (Foundation)?

Please bear with me as I am very new at SharePoint (2 weeks in). We have SharePoint 2013 (Foundation), SharePoint Designer 2013, and Office 365 with InfoPath. How do I use the three together? I need to make forms with SharePoint Designer and InfoPath, but there isn't an option for InfoPath from Designer (I think because it is Foundation?). When I was watching a video I they clicked on an InfoPath icon in the ribbon, however, I don't have one. Any guidance would be greatly appreciated.