Can we overload and override main method in java

Can we overload main() method in java:
Yes we can !!

But only public static void main(String[] args) will be used when your class is launched by JVM , as :- 

But it will always print main(String[] args)

public class Test {
    public static void main(String[] args) {
        System.out.println("main(String[] args)");
    }

    public static void main(String arg1) {
        System.out.println("main(String arg1)");
    }

    public static void main(String arg1, String arg2) {
        System.out.println("main(String arg1, String arg2)");
    }
}

We can call the main() method yourself from code, of course - at which point the normal overloading rules will be applied. 
Note that you can use a varargs signature, as that's equivalent from a JVM standpoint: -
public static void main(String... args)

Can we override the main method in java

No!
main is a static method, and is thus not polymorphic. You may hide it be defining another static main method in a subclass, though.