All occurrences of "you" refer to the people of Israel. Moses was included as a part of the people. Alternate translation: "we are a nation ... has chosen us"
Yahweh choosing the people of Israel to belong to him in a special way is spoken of as if Yahweh set them apart from all other nations. This can be stated in active form. Alternate translation: "Yahweh your God has set you apart from other nations" (See: [[rc://en/ta/man/jit/figs-metaphor]] and [[rc://en/ta/man/jit/figs-activepassive]])
This means basically the same thing as the first part of the sentence. They both mean that the people of Israel belong to Yahweh in a special way. (See: [[rc://en/ta/man/jit/figs-parallelism]])