Very good question. A baby come from woman’s belly. Originally the baby is just a single cell, with half of its genetic material from its mom and the other half from its dad. This single cell develop and grow into a baby inside a woman. When the baby feels ready, it comes out from the woman (its mother).
Gametes are sex cells that contain only half of the chromosomes compared to the other cells in the body. The gametes of the mother and father are fused to become the zygote, the cell containing the full set of chromosomes (half from the mother and half from the father). Later this zygote, completes cell divisions to become the embryo, which later develops into a baby.
Very good question! There is excellent information here already. I’ll just add a bit to the story. Both men and women produce gametes, often referred to as sperm and eggs. Typically, babies are made when men and women have sex. A mans sperm enters a woman’s body and successfully fuses with a woman’s egg, then it may become a zygote and develop into a fetus in the woman’s uterus. After an average development time of 9 months, the woman gives birth to a baby. If you have more questions about this topic make sure to ask your parents!