Gabriel said the ram with two horns represents the kings of Media and Persia. The goat represents the king of Greece, and the great horn between its eyes is its first king. Daniel 8:20–21
In Daniel 8:20–22, the interpretation moves from imagery to identification. The two-horned ram stands for the kings of Media and Persia. The rough male goat stands for the king of Greece, and its large central horn represents the first king. These verses sit inside Daniel’s vision-and-explanation sequence in chapter 8.
Daniel 8:20–22 shifts from symbols to plain identification. The ram with two horns “is” the kings of Media and Persia. The goat “is” the king of Greece. The large horn between the goat’s eyes represents the first king. When that horn is broken, four kingdoms arise from the same nation, but they do not have the same power.
A careful answer keeps the immediate passage, the book's argument, and the whole-Bible storyline together, so the question is answered in context instead of as a detached idea.
Start with Daniel 8:20-21, then read the surrounding section so the answer stays connected to the passage's flow.
20The ram which you saw, that had the two horns, they are the kings of Media and Persia.
21The rough male goat is the king of Greece: and the great horn that is between his eyes is the first king.