I found that ReveriaExplorer is good for information on specific items, as well as this guide helping me out as a whole. ;o
To unlock Origin Island, you need to have completed the story, be Lv. 50 and have befriended both Yuelia and Noelia. (This happens automatically at Lv. 45 anyway) You should be able to "advance" the story as normal by talking to Flutter (Or, if you're playing the American version, Butterfly) in your house.
Also note: If you've got the Origin Island DLC installed onto your save file, you can't play online with those who don't have the DLC, even if you haven't gone to Origin Island yet.
Terraria, Minecraft 1.14.4, Monster Hunter World Iceborne, Deep Rock Galactic, Hades