There are many more apples on the plate. Use many when you can count the items, and much when it's an uncountable quantity.

The correct sentence would be: "There are many more apples on the plate." 1. Many is mainly used with countable nouns like Apple, Book, Photograph, Candle, Painting etc. 2. Much is used with uncountable things like Stars, Rice, sugar, water, cheese, etc.

many for countable things much for uncountable things