Genesis 11:7

God said, ‘Let us go.’ He did not say, ‘I will go.’ Perhaps he said ‘us’ because he is 3 persons. He is the Father and the Son and the Holy Spirit. And he is also one God. But it is more likely that this is not the reason. The *Hebrew word that means ‘God’ is like a plural word. Perhaps that is why God called himself ‘we’. (See Genesis 1:26 and the comment.)

We do not know how God confused their language. It is possible that people spoke different languages. But they all spoke one language in addition to their own languages. (See verse 1 and comment.) So perhaps when God confused their language he made them forget that one language. Therefore, they could not understand each other.

v8 So the *Lord made the people stop building the city. He made them scatter from there. And they scattered over the whole surface of the earth. v9 Therefore it was called Babel, because there the *Lord confused the language of all the earth. And the *Lord scattered them over the whole surface of the earth.