Unlike many items in Minecraft, saddles cannot be crafted using a crafting table. You'll need to find them pre-existing in the game world through various methods:
Fishing: This is a common way to get a saddle. While fishing, there's a chance you'll reel in a saddle along with the usual fish and junk. To improve your chances, you can use an enchantment called "Luck of the Sea" on your fishing rod.
Chest loot: Look for saddles in various chests scattered throughout the world. These include chests in:
Trading with villagers: Leatherworker villagers have a chance to sell you a saddle for emeralds once they reach the master level in their profession. However, this is not guaranteed and may require some patience and resources.
Killing a Ravager: These spiky, hostile mobs found in raids will always drop a saddle when defeated. This can be a risky but reliable way to get a saddle, especially if you have proper armor and weapons