Question

1. You need a room more than I need a study.

2. You need a room more.
3. You need a room a lot.
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Are they all grammatical?
Did 'more' come from 'much'?

Answer 1

1 is fine, but 2 and 3 don't make sense.

'More' is a word used when making comparisons.
'Much' is an adjective used to indicate quantity.