Learn Kotlin by solving problems from Project Euler.
The easiest way to get started with Kotlin is to download IntelliJ.
You can also use the following netbeans plugin. http://plugins.netbeans.org/plugin/68590/kotlin
To create a Maven project you can use the kotlin Maven archetype.
$ mvn archetype:generate -B -DarchetypeGroupId=org.jetbrains.kotlin \
-DarchetypeArtifactId=kotlin-archetype-jvm \
-DarchetypeVersion=1.2.21 \
-DgroupId=com.company \
-DartifactId=project \
-Dversion=1.0-SNAPSHOT \
-Dpackage=com.company.project
Read Kotlin tutorials and the language spec here at kotlinlang.org.