Question

not know the first thing about是什么意思

Answer 1

not know the first thing about
对…一无所知

If someone says they don't know the first thing about something, they do nothave even an elementary knowledge of the subject.
如果有人说他们对做某些事情一窍不通就表示他们在此领域连最基本的常识都没有。

So the revelation that he literally doesn’t know the first thing about the debtcrises currently in progress is, as I said, interesting — and not in a good way.
瑞安先生的讲话表明，在目前进展中的债务危机方面，毫不夸张地讲，他连最基本的都不懂。 所以，正如本人前面所说，这种事情很有意思——但并不是好事。

If you are not a chemist, the first basic thing that you should know about physicsand chemistry is that electrons are the things that hold atoms and moleculestogether.
如果你不是个化学家，那么有一点最基本的物理化学知识就是原子和分子是由电子联系在一起的。

Answer 2

not know the first thing about[英][nɔt nəʊ ðə fə:st θiŋ əˈbaut][美][nɑt noʊ ði fɚst θɪŋ əˈbaʊt]
一无所知;

例句:
1.
I do not know the first thing about the law suit.
我一点儿也知道这件诉讼案的事。

2.
Do you know the first thing about holding up america?
你知道治理美国最重要的事情么？