Okay little one, Maaseh Breishit and Maaseh Merkavah are two important Jewish concepts to understand.
Maaseh Breishit means "the act of creation" in Hebrew. It is the story of how God created the world in six days and rested on the seventh day, which is Shabbat. This story is told in the first book of the Torah, which is called Genesis.
Maaseh Merkavah, on the other hand, means "the act of the chariot" in Hebrew. It is a mystical concept that involves a person journeying through the heavens to the throne of God. It is also known as "Merkavah mysticism."
Both Maaseh Breishit and Maaseh Merkavah are important to Jewish tradition because they help us understand our relationship with God and how the world works. They remind us that God created the world and that we are all connected to each other and to God.
So, in summary, Maaseh Breishit is the story of how God created the world, and Maaseh Merkavah is a mystical concept that involves a journey through the heavens to the throne of God. Both are important in Jewish tradition and help us understand our relationship with God and the world around us.