The prohibitions of Yom Kippur are formulated by the Torah in positive terms (“You shall afflict your souls”), not as prohibitions (e.g., “You shall not eat”). What are the ramifications of this?
The mitzva of Brit Mila was given to Avraham and his descendents as part of the covenant with God. When Avraham was ninety-nine years old, God promised him that he would be the progenitor of a nation that would receive the land of Israel as an everlasting possession.
Halakha indeed obligates a father to support his children. The basic obligation seems to be a Biblical obligation according to the Rambam and a rabbinic obligation according to the Ramban.