If you'd like to block off full days for the entire team, from the dashboard, go to Calendar > go to the specific day you'd like to block off > drag and drop from the start time to the end time > on the right hand side, select "non-working time" on the right hand side

In the right hand side of your screen, a new menu will pop up. Select "Nonworking Time"

Add a Non-working title into the Notes field on the right hand side menu to let your staff know why time is booked off for this occasion and click Update.