How to distinguish between countable nouns and uncountable nouns in English

How to distinguish between countable nouns and uncountable nouns in English

Most words are countable nouns, only a few are uncountable nouns, so uncountable nouns need to be remembered

On English countable nouns and uncountable nouns
meat ,vegetable ,apple ,beef ,carrot,chicken ,juice ,melon,milk,onion,orange,pork ,potato,water,water ,drink,food ,egg
countable noun:
Uncountable noun:
Come on, hand it in tomorrow

Countable nouns: vegetable, apple, carrot, orange, potato, egg, melon, onion,
Uncountable nouns: meat, beef, chicken, juice, milk, water, drink, food, pork, orange (orange juice)

Talk is a noun and show is also a noun. Isn't it an adjective that modifies a noun / why is the phrase talk show

A noun can be used as an attributive to modify a noun. The noun used as an attributive usually describes the material, use, time, place, content, category, etc. of the noun

Are numbers nouns or adjectives?
Like the numbers 1, 2, 3
Are these nouns or adjectives?

Numbers are neither nouns nor adjectives. They are listed separately as numerals