You can easily update your availability calendar (Available dates, Closed, Booked and Tentantive) on every rental by selecting the "Calendar" tab.
Then, you can just click-and-drag with your mouse, the dates you want to edit.
Then, you set the status and price. If you want to set the available dates, select the status "Available" and set the daily price in euros. If you want to set a "Pending" status, you can add the daily offered price for your info. The same for the "Booked" days. Finally, you can set the dates when your property is "Closed"
You click "Save" and you see the "Changes have been saved" message. That means that this info has been stored. Click "Close" and go to the next period.