Question

how MANY is numberable and MUCH is measurable.DISCUSS ITS USAGE

Answer 1

Many: you use it when you can count whatever you're referring too
Much: you use it when you can't count the individual things you're referring too

Examples:
MANY:
-How many glasses of water did I drink? (I can easily count how many I drank)
-There are many eggs in that nest. (Again, we can count the number of eggs)
-I went to the ice cream parlour and there were so any flavours to choose from! (Again, we are able to count the flavours).

MUCH:
-How much soup did you eat? (This is hard to count. Can you count how much liquid you ate? Not really, because you can't really count each "soup molecule" per say. .....
However, you CAN say: "How MANY" bowls of soup did you eat?" Now, we are able to count the number of bowls of soup we ate easily. But, if you're talking about just 1 bowl and how much you ate from that bowl... then it's hard to count how much soup was consumed.)

-My waiter put too much spaghetti on my plate. (Now, although you could technically count how many spaghetti noodles are on your plate... you're not actually going to count it. So, that's why we use "much" here.)

Recap:
Use "many" when referring to discrete quantities (ones you can count).
Use "much" for continuous quantities (such as time, volume) or when it's "too hard" to count, like in the spaghetti example.