This is very Simple, Just get month of both of dates which dates you want to compare but both dates should be in date format or you have to cast in date format
get month of any date MONTH() method
it will return only month of this date, just pass date in month method.
if your date in varchar or string format than you should cast in date format
Complete Example Is
MONTH(CAST(YourDate AS DATE)) = MONTH(GETDATE())