Hi Ashar,
Please check out the following documentation:
https://docs.mendix.com/refguide/parse-and-format-date-function-calls
It allows you to format a DateTime attribute / variable in any string format.
Current Date can be pulled as ''[%CurrentDateTime%]''
Below is an example where the condition is to ensure the Month of user's date of birth is same as month of current date:
DATEDIFF(MONTH, User.DateOfBirth, ''[%CurrentDateTime%]'') = 0