Grass Block is a fundamental building unit characterized by its green, pixelated top layer, which resembles grass, and a dirt-like texture on the other five sides. It's commonly found on the surface of most biomes and can be harvested with or without a tool. When a block is placed in a location with adequate light, the grass will spread to adjacent dirt blocks, transforming them into grass blocks as well.
The numerical item ID for Grass Block is 2
Numerical item IDs will only work in Minecraft versions below 1.13.
The item ID for Grass Block is minecraft:grass_block
This is the spawn command to give yourself Grass Block in Minecraft which includes the Minecraft /give command. If you are using the Essentials plugin you will need to use /minecraft:give instead of /give