Word inclusion

You should say:

Do you want to have six-pack abs?

No "a" at all.

Doctor DYou should say:Do you want to have six-pack abs? No "a" at all.

Thanks. Does the same apply for the second sentence?

Yes.
It's like saying: Do you want pasta for dinner? (No article needed).

Anonymous'a' six pack abs?

Abs is plural. It is wrong to use the indefinite article (a) with a plural noun.

Doctor DYes. It's like saying: Do you want pasta for dinner? (No article needed).

I see. Thanks. But you need the 'a' with sandwich or burger: Do you want (a) sandwich for dinner? (Is the article needed here?)

As the earlier post said: Plural.

So the difference is
Do you want pasta for dinner? (pasta is a plural noun)
vs
Do you want a bowl of pasta for dinner? (a single bowl).

Doctor DAs the earlier post said: Plural.So the difference isDo you want pasta for dinner? (pasta is a plural noun)vsDo you want a bowl of pasta for dinner? (a single bowl).

I see. So 'a' should be used with sandwich but not sandwiches, right?

Doctor D? (pasta is a plural noun)

I'd say it was uncountable in English. The pasta is tasty,

fivejedjon Doctor D? (pasta is a plural noun)I'd say it was uncountable in English. The pasta is tasty,

I see. And should 'a' be used with sandwich? (Do you want 'sandwich' or a 'sandwich' for dinner)

Also, if I use 'sandwiches' should the 'a' be excluded?

AnonymousAnd should 'a' be used with sandwich?

Yes.

AnonymousAlso, if I use 'sandwiches' should the 'a' be excluded?

Yes. You may use zero-article or 'some'...or 'two'.