I need help on the indefinite article "a".

If I say, "Liverpool is a big football club", does it mean that "Liverpool is a big club in size"? or

does it mean "Liverpool is one of the big clubs in the World". Even though, I think it's depending on how I say or how I mean, I just want to be sure about this.

By the way, you can't really say, "Liverpool is big football club"? (without "a") or if you can say such a phrase, does it mean "Liverpool is a big football club in general"? It seems a little strange though.

If I say, "I am going to Library", does it mean that "I am going to read/study in a certain place"? like in "I am going to school", and

if I say, "I am going to a library", does it mean "I am going to any library?"

Thanks in advance.
"... is big football club" and "... going to library" are impossible.

A noun which is singular and countable must have a determiner, usually "a(n)" or "the". There are a few exceptions, as in "... going to school", but not many.

If the noun is not singular ("... are big football clubs") or the noun is not countable ("... is good butter"), the rule does not apply, and a determiner is not required.

If you say "I'm going to a library" (not a common thing to say, by the way), you mean one of the following:

"I'm going to a certain library I have in mind but am not mentioning specifically".
"I'm going to any library, it does not matter which library."

Without context, I would probably think of the second as the meaning.

The same two interpretations are available for most similar uses of "a(n)":

"I'm going to buy a house".

If you already know which house you are going to buy, this means "I'm going to buy a certain house, a particular house". If you don't already know which house you are going to buy, this means "I'm going to buy some house, one of the many houses that may be available for me to buy."

Just to pick up on the 'big' question: in a Liverpool context, it would mean 'a big football club' as in 'a very famous football club', or 'a football club with a long and impressive history', or 'an important football club'.

If you were talking about a 'club' in a social context, though, it would probably mean 'having a lot of members':

1. Our book club is quite big = lots of people belong to our book club.

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Thanks Jim.
It really helped!
 MrPedantic's reply was promoted to an answer.
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