20 19 leap year or no leap month. What month?

20 19 is not a leap year. Generally, a year divisible by 4 is a leap year, and a year divisible by 4 is a normal year. Speaking of century years (that is, the whole hundred years), only leap years can be divisible by 400, otherwise it is a normal year. Accordingly, 20 19 is not divisible by 4, so 20 19 is not a leap year, but a normal year, and there is no leap month.