How to Find Minerals
Coal, you need it or charcoal to heat your furnace, or make glass, maybe even cook some food. Coal is the most often found mineral in the game, and can usually be found anywhere, but sometimes lurk near underground water or lava.
Let's face it, Gold isn't worth much. It's decorative, but the equipment isn't very good at all. If you want to find gold, like coal, it can be found randomly throughout the underground, or a certain distance close to lava.
Iron is one of the more useful minerals in the game, and is slightly more rare than coal, but less rare than gold. It can be found near lava and randomly throughout your maze of tunnels.
Redstone, useful for linking things together, for using levers on pistons. Redstone can be found plentiful near lava, and sometimes elsewhere. Keep in mind you need an Iron pickaxe or higher to mine Redstone without breaking it.
Diamonds are quite rare, but make tools last much longer, and make beautiful and protective armor. Diamonds are most likely to be found near lava, but can be found in random places.
Obsidian is used for the Nether portal, and can be made by combining water and lava. Will always be found near water and lava, and can only be mined with a diamond pickaxe.
Dig down until you hit something gray.
Thanks for reading, if I forgot anything comment or message and I'll credit you to helping me remember.