I always thought of Tabernacle as the church building. But a quick google tells me in Catholic churches it’s a container where the communion (bread, wine) is kept.
Your quick search is mostly correct; when we (Catholics) say “Tabernacle”, we’re either referring something the ancient Hebrews used or to the “gold” (usually, polished brass) box usually found front and center in a Catholic church.
I understand that you’re Protestant, and that your theology of the Eucharist is different from ours. I don’t wish to have that argument here; it has been done to death on this forum.
From our (Catholic) perspective, the consecrated host IS Jesus Christ Himself, hidden under the appearance of unleavened bread. The same is true of the consecrated wine. Some of the consecrated host is kept in the Tabernacle after Mass; the consecrated wine is always consumed. Therefore, from our perspective, to face the Tabernacle is literally to face God Himself. For this reason, we Catholics (should) always make a gesture of reverence toward the Tabernacle when entering a Catholic church, and it is appropriate for the Priest, along with the congregation, to face the Tabernacle during Mass.