Christmas is not tied to the Hebrew calendar.
Since it's tied to the Western calendar, it falls on a different date every year on the Hebrew calendar. (The opposite of Jewish holidays, which are the same date every year on the Hebrew calendar, but different dates on the Western calendar.
Here are Hebrew Dates for Christmas for the next 5 Years:
2013 = 22 Tevet 5774
2014 = 3 Tevet 5775
2015 = 13 Tevet 5776
2016 = 25 Kislev 5777
2017 = 7 Tevet 5778
Jesus' birthday is not marked in the Jewish calendar.
The Gregorian Calendar is solar and the Hebrew Calendar is lunisolar.
In the Hebrew calendar, the month of Av is followed by the month of Elul.
1 week = 1 week on the Hebrew calendar. (The Hebrew week is the same length as the week on the Western calendar)
There isn't any festival celebrated along with Christmas as per the Hebrew calendar, since Christmas is not tied to the Hebrew calendar. (So every year, Christmas falls on a different date on the Hebrew calendar).
The Hebrew calendar is used in Israel, and by Jews all over the world.
The individual you are referring to is likely Jesus Christ, whose birthday is celebrated as Christmas on December 25th. He is a central figure in Christianity and his teachings have had a profound impact on the development of Western culture and society. His birth is considered a turning point in the calendar, as it marks the beginning of the widely used Gregorian calendar.
A Hebrew calendar website can help you with that.
In the Hebrew calendar, the month of Nissan immediately precedes Iyar.
The Hebrew month Adar is the same in all countries. It is a Spring month.
The tenth month in the Hebrew calendar is called "Tamuz". It usaually falls out around July time.
April is not a month in the Hebrew calendar, and the Sundays in any Hebrew month could easily change from year to year, just as they often do for any month in the civil calendar.