Setup of basic gradle using cli:

gradle init --use-defaults --type java-application

The above command will setup a basic gradle project

./gradlew build

To prepare a jar which is executable, you need to setup manifest property in build.gradle to identify what is the main class to execute

jar {
    manifest {
        attributes (
            'Main-Class': 'org.example.Main'
        )
    }
}

The above command can build your project

./gradlew jar

The above command creates a new jar file in build/libs folder

java -jar build/libs/filename.jar

The above command will execute your code

Homework

Try to build a jar and run it directly from cli and see if the okhttp code is working or not just like it is working by running directly from intellij
instead of okhttp try to integrate retrofit library to make the same http call