The answer to this is likely to be no! Most employers will have specific arrangements in place for booking leave and this will usually require you to give a certain amount of notice of any request to take annual leave. Any such request will be subject to your employer's approval.
It is likely that you will also have to complete some kind of leave booking form as well. Your employer will need certain minimum levels of staffing to run the business and therefore, granting requests for annual or unpaid leave needs to be coordinated and planned.
Your contract of employment or employee handbook should set out the rules for booking time off in your particular workplace.
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