Answer 1

The main() method is the starting point of the program. JVM start execution with this method.

public : to be visible by JVM

static : no instance of class contain main method have to be created to run main()

void : don't return any value

main() : method signature searched by JVM

String[] arg : Can pass argument to java when running program, to load test or production parameters for exemple

https://www.baeldung.com/java-main-method