Once you unlock the MyCastle feature, you are given two resource gathering points: One a local food of the region, and one a local mineral. In Revelations , you have access to all the types of food and mineral gathering points. You can gather at these points once every day. You can gain different resources from characters finding food or rocks on the ground, visiting other MyCastles, or prizes from the Lottery Shop. These resources are used for various MyCastle features, such as purchasing Accessories, cooking meals, feeding Lilith, etc.
Ores are associated with a specific weapon of the region, and are used to forge that weapon.
Foods are associated with a certain stat, and will be what gets boosted if used in the Mess Hall or feeding Lilith.