The deck is designed to show you 28 new cards per day. On day one, you'll finish those fairly quickly. But as you keep going, your old cards will come back to help you review and remember, and so your total time spent per day will increase to somewhere around 15-30 minutes every day.
Note: As of September 12th 2019, we no longer provide official support for our Anki based pronunciation trainers and word lists. You are more than welcome to still purchase and use them, but the support we are able to offer for these products is limited. For supported languages, these materials are already built into the Fluent Forever app.