How to make and use maps in Minecraft
Craft an Empty Map, use it and walk around to fill it in, then zoom, copy and lock it at a Cartography Table.

An Empty Map is a blank map waiting to be filled: use it and it becomes a Map that draws the area around you as you explore. It is crafted from Paper and a Compass.
It is made with the Crafting Table from 8 × Paper and Compass.
When you use it, the map is centered on a fixed grid of the world, not exactly on you, and it starts drawing what you can see from above. Keep it in hand while walking to fill in the terrain.
Empty Maps are also used at the Cartography Table to copy an existing map, and Cartographer villagers sell them.
Several Empty Maps can be kept in a stack, so you can carry a few and start a new map whenever you leave the edge of the current one.
8 × Paper + Compass → Empty Map
// Slots with several items cycle through every accepted option.
Craft an Empty Map, use it and walk around to fill it in, then zoom, copy and lock it at a Cartography Table.
At the Crafting Table: 8 × Paper and 1 × Compass give 1 × Empty Map. It can be found as loot in Abandoned Camp, Village, Shipwreck and Stronghold. Sold by Villager: Cartographer (Novice). Hero of the Village gift: Villager.
Using it creates a Map of the area around you.