The word 'enough' is not a noun. The word enough is an adjective, an adverb, and an indefinite pronoun, which takes the place of a noun for an unspecified amount. Examples:
Adjective: We've made enough Sandwiches for an army.
Adverb: He thought enough about how to solve that problem.
Indefinite pronoun: You've written three pages, I think this is enough.
The noun sheet is a countable noun. The plural form is sheets.
Yes, the noun 'tool' is a countable noun, the plural form is tools.
countable
The noun skill is a countable noun; a skill or many skills.
The noun 'Celt' is a countable noun; the plural form is Celts.The noun 'Celt' is a concrete noun; a word for a person.
Yes, the noun 'steak' is a countable noun; one steak or enough steaks for everyone.
Yes, the noun 'taco' is a countable noun, the plural form is tacos.Example: One taco will not be enough. Get two tacos for me.
The noun 'hill' is a countable noun. The plural form is 'hills'.
Shark is a countable noun.
Prawn - prawns is the plural - is a countable noun
Transport is both countable and uncountable as a noun.
Yes, property is a countable noun.
The noun 'animal' is a countable noun. The plural form is animals.
Yes, the noun 'marriage' is a countable noun. The plural noun is marriages.
The noun meeting is a countable noun; for example: We have a meeting this afternoon. We've had two meetings already this week.
The noun 'desert' is a countable noun; the plural form is deserts.
The noun analysis is a countable noun; the plural form is analyses.