Quick answer
Find moss in lush caves or under the root blocks of azalea trees, then break the moss block to pick it up (no silk touch required). To make large patches fast, place moss blocks and use bone meal on them to spread moss to nearby blocks.
Step-by-step (Survival)
- Locate a lush cave or azalea: Lush caves are underground biomes with dripleaf, glow berries, spore blossoms and lots of vegetation. You can also find moss under the roots of azalea trees (sometimes visible from the surface where an azalea sits over a cave).
- Find moss blocks: Moss appears as patches of moss blocks and sometimes moss-covered stone on the cave floor and walls or beneath azalea roots.
- Mine the moss: Break moss blocks with any tool or by hand — they drop themselves as an item, so you can pick them up and carry them back to your base.
- Spread moss: Place one or more moss blocks where you want moss. Use bone meal on a placed moss block to make it spread to nearby eligible blocks (stone, dirt, etc.). Repeated bonemealing quickly turns an area into mossy ground.
Other ways
- Creative Mode: Open the inventory and search for "moss" and place as many moss blocks as you want.
- Cheats/Commands (if enabled): You can give yourself moss blocks with a command. Example (Bedrock/Java-compatible format):
/give @p moss_block 64(or use the creative inventory).
Tips
- Bonemeal is the fastest way to turn a large area into moss once you have a few moss blocks.
- Bring shulker boxes or ample inventory space if you plan to harvest a lot.
- Moss blocks are useful for decoration, landscaping, and making moss carpets/decoration (use the creative inventory or crafting in versions that support moss carpet).
If you want, tell me your Bedrock version and I can give any version-specific details or a step-by-step for finding lush caves near your world spawn.