How to send reminder email with condition ?

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MySQL

email

stored-procedure

So i would wanted to send a reminder email if reach 2 days before the Actual Date.
Example: Assuming today is 8th & the Actual Date is 10th so it will send a reminder email out.

So i've write the email store procedure, it is able to send but i need to add the condition which i mentioned on above

What I have tried:

IF Action = 'Reminder Mail To Customer' THEN
  set Content = (SELECT CONCAT('<p>Dear ',a.Name,',</p><p> This is to remind that the your birthday ',a.BirthDate, ', is almost here ,do visit us & get ',b.Dis.' discount from us.</p> <p>Sincerely,<br>YOURS WW</p>') FROM customer_dtl a inner join percentage_dis b on a.ID = b.DisID  WHERE a.ID = Get_Id and b.ID = Get_ThisId);
  set Subject = (SELECT CONCAT(a.CusNo,' Reminder Mail To Customer') FROM customer_dtl a WHERE a.ID = Get_Id);
END IF;