When you launch the game, you will see the main menu, where you can choose to play in singleplayer or multiplayer mode, or access other options and settings. To create a new singleplayer world, click on Singleplayer, then Create New World. You will see a screen where you can name your world, choose a game mode, and customize some world options.

The game mode determines the difficulty and rules of the game. There are four game modes:

• Survival: This is the default and most common mode, where you have to gather resources, craft items, build structures, and fight enemies to survive. You also have a health bar and a hunger bar that you need to maintain. If you die, you will respawn at your spawn point, but you will lose all your items that you were carrying.
• Creative: This is a mode where you have unlimited resources and can build anything you want without any restrictions. You also have the ability to fly and are invulnerable to damage. This mode is good for experimenting and designing.
• Adventure: This is a mode where you can only interact with the world in certain ways, such as using tools or buttons. This mode is designed for custom maps and scenarios that have specific rules and objectives.
• Hardcore: This is a mode where you play in survival mode, but with the highest difficulty and permadeath. If you die, your world will be deleted and you cannot respawn. This mode is for experienced and challenge-seeking players.

You can also choose a difficulty level, which affects how hostile the mobs (creatures) are and how fast your hunger bar depletes. There are four difficulty levels:

• Peaceful: This is the easiest level, where no hostile mobs will spawn and your hunger bar will not deplete. This level is good for beginners who want to learn the basics of the game without any danger.
• Easy: This is a level where hostile mobs will spawn, but they will deal less damage and have less health. Your hunger bar will deplete slowly and you can heal by having a full hunger bar.
• Normal: This is the default level, where hostile mobs will spawn with normal damage and health. Your hunger bar will deplete at a moderate rate and you can heal by having more than half of your hunger bar full.
• Hard: This is the hardest level, where hostile mobs will spawn with more damage and health. Your hunger bar will deplete faster and you can only heal by using potions or golden apples.

You can also customize some world options, such as the world type, the seed, and the cheats. The world type determines the shape and features of the terrain. There are several world types, such as default, superflat, large biomes, amplified, and custom. The seed is a code that determines how the world is generated. You can enter a specific seed or leave it blank to get a random one. The cheats are commands that you can use to change the game rules, such as changing the time, weather, game mode, or giving yourself items. You can enable or disable cheats when creating the world, but you cannot change it later.

Once you have chosen your settings, click on Create New World and wait for the world to load. You will spawn in a random location, usually near the center of the map. The world is divided into different biomes, which are regions with different climates, landscapes, and resources. Some common biomes are plains, forests, deserts, mountains, oceans, and swamps. You can explore the world and find different biomes, but be careful not to get lost.