I'm trying to run "gradlew setupDecompWorspace" in the extractet 1.12.2 forge file but it says Build Failed and I don't know why.

I have the latest version of jre and jdk. I started modding a few hours ago so I maybe be doing something obvious wrong

 

here's the "logs"

 

C:\Users\###\Desktop\Minecraft Modding\Forge 1.12.2-14.23.5.2854>gradlew setupDecompWorkspace
To honour the JVM settings for this build a new JVM will be forked. Please consider using the daemon: https://docs.gradle.org/4.9/userguide/gradle_daemon.html.
Daemon will be stopped at the end of the build stopping after processing

> Configure project :
New Dep: net.minecraftforge:forge:1.12.2-14.23.5.2854_mapped_snapshot_20171003-1.12

FAILURE: Build failed with an exception.

* What went wrong:
Task 'setupDecompWorkspace' not found in root project 'Forge 1.12.2-14.23.5.2854'.

* Try:
Run gradlew tasks to get a list of available tasks. 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

Deprecated Gradle features were used in this build, making it incompatible with Gradle 5.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/4.9/userguide/command_line_interface.html#sec:command_line_warnings

BUILD FAILED in 7s

 

Forge 1.12 is no longer supported on this forum.

Please update to a modern, supported version (1.14.x).