How to understand the building of the third Temple in Jerusalem, as symbolic or direct meaning? whats the main purpose of it?

There will literally be an actual Third Temple, as seen explicitly and in practical detail, in the last chapters of the prophecies of Ezekiel, and as we are commanded as one of the eternal 613 mitzvot, regardless of whether it will be before or after the Mashiach. Whether there will be animal sacrifices there, see my answer at: Rav kook and Korbanot- animal sacrifices-in future Temple It will definitely serve as a central focal point of prayer and unity not only for the Jewish people, but for all mankind, “for My House will be called a House of Prayer for all the nations” (Yishayahu 56, 7(, as well as place of unity and meeting for all Israel during the 3 annual festivals. .