Life is full of choices, so I must learn to make good ones. In this phrase "life" and "I" are nouns but is "ones" considered a noun also because is used as number or no??

Answer 1

"Life" is a noun, but "I" is a pronoun. The word "one" is a pronoun, too.

http://grammar.ccc.commnet.edu/grammar/pronouns1.htm >>> http://grammar.ccc.commnet.edu/grammar/one.htm

Answer 2

There's another noun in there, though, that you missed. Can you find it?