PoE 2 Ancient Vows Quest unclear

I have been running around in Act 2 for the last several days. Keep seeing somethign that says "place the relic on the altar that you found." Haven't found an altsr? Not sure if I have found an altar? Running around killing guys. What is an altar? Find other icons to click on. Eyes light up but still don't get completion. Click on a thing that says its an altar but nothing happens. I get an empty star-shape diagram. Nothing happens when I click on it.

Find out days later I'm supposed to drag a thing from my inventory TO the diagram (after clearing the map multiple times with no progress). Only to have it tell me I need some other thing.

Suggestion: maybe when click on the altar/diagram it prompts you to find an item in that is in your inventory if you have it? This was REALLY unclear to me. I mean, maybe I'm dumb but I was expecting that If I clicked on somethign that it would tell me what I was supposed to put there rather than just leaving a blank interface. =(

The items you need are guaranteed drops from packs next to the bosses of their respective zones if you don't have one in your inventory already (they can drop from other packs in the same zone). You should have them already by the time you get to the Valley of the Titans.

The quest needs better explanation and hints on - where the items can be dropped from. Why should I go to google to find item drop areas?