Dear friend,
When you have questions about "Many and Much", you need to know about the count nouns and non-count nouns too. ;)you may say:
How many books do you want to buy?
Many students have taken the test last week.
but,
How much flour is needed to bake a cake?
How much money do you make in a year?
MUCH precedes non-count nouns but MANY will be used with countable nouns.
About MORE I should say it is for comparison, if you use the adjectives with one syllable you will have sentences as below:
- She is younger than what she looks.
- They are older than us
But if the adjectives have more than one syllables then:
- He has bought a more expensive car.
- They are more patient than our teachers.
I hope this would help.
;)