It is uncountable.
Can you have 3 food? No.
The best way to check is to compare it to money and dollars.
Money is uncountable and dollars is countable.
I can have 3 dollars, but not 3 money.
Transport is both countable and uncountable as a noun.
countable
Uncountable
uncountable
uncountable
The gerund painting is a countable noun, as in "There are 12 paintings in this room."
few is countable
countable
Countable
The noun 'steel' is an uncountable (mass) noun, a word for a substance.
he asked me if the word fire wood countable or uncountable?
Countable