To know the differences, you need to make the differences between much and many.
Much: uses with nonnount nouns. Ex: much water; much bread; much pizza.
Many: uses with count nouns. Ex: many children; many people; many students.
Now, we can say:
- How much?: is used to ask about noncount nouns.
Ex: How much water does do you want? Resp: i want a cup, please.
How much does it cost? Resp: It costs five pesos.
- How many: is used to ask about count nouns.
Ex: How many students are there in the classroom? Resp: There are 10 students.
