Cant make mob a creature type

When i try to set my mob as a "creature" type i get shown this issue, im not sure what to do to fix this as im new to this completely 


Executing Gradle task: build
Build info: MCreator 2023.3.36712, forge-1.20.1, 64-bit, 8023 MB, Windows 11, JVM 17.0.7, JAVA_HOME: C:\Program Files\Pylo\MCreator\jdk, started on: 2023-10-20-15:57:39

> Task :mcreatorLink UP-TO-DATE
> Task :compileJava FAILED
C:\Users\44793\MCreatorWorkspaces\mocreatures_reborn\src\main\java\net\mcreator\mocreaturesreborn\entity\TurtleEntity.java:221: error: cannot find symbol (entityType, world, reason, pos, random) -> (world.getBlockState(pos.below()).getMaterial() == Material.GRASS && world.getRawBrightness(pos, 0) > 8));
^
symbol: method getMaterial()
location: class BlockState
C:\Users\44793\MCreatorWorkspaces\mocreatures_reborn\src\main\java\net\mcreator\mocreaturesreborn\entity\TurtleEntity.java:221: error: cannot find symbol (entityType, world, reason, pos, random) -> (world.getBlockState(pos.below()).getMaterial() == Material.GRASS && world.getRawBrightness(pos, 0) > 8));
^
symbol: variable GRASS
location: class Material
2 errors
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':compileJava'.
> Compilation failed; see the compiler error output for details.
* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.
* Get more help at https://help.gradle.org
BUILD FAILED in 4s
1 actionable task: 1 executed

BUILD FAILED
Task completed in 7 seconds