How to start comparison when I have values inside BST?

Question

I'm trying to sort a BST alphabetically and I wrote an insert method if compareTo==-1 it goes to root.setLeft() if compareTo==1 goes to root.setRigth() but obviously when I run the program it doesn't start with any value so it's null and I'm getting NullPointerException, I know I have to start the comparison after I values but I can't figure out how to do that, also if I put a valid value in the constructor it doesn't insert values after that.

class BST{

    Node insertNames(Node root, int data, String name, double salary){
                if(root==null){
                    root=new Node();
                    root.setData(data);
                    root.setName(name);
                    root.setLeft(null); root.setRight(null);    
                    }else{
                        if(name.compareTo(root.getName())==-1) root.setLeft(insertNames(root.getLeft(),data, name, salary));
                        else if(name.compareTo(root.getName())==1) root.setRight(insertNames(root.getRight(),data, name, salary));
                }
                return root;
            }    

 void printInorder(Node node) 
        {
            if (node == null)
                return;

            /* first recur on left child */
            printInorder(node.left);

            /* then print the data of node */
            System.out.print(node.getName() + " ");

            /* now recur on right child */
            printInorder(node.right);


        }

}

class Node{

int data;
    Node left;
    Node right;
    String name;

    public void setName(String name){
        this.name=name;
    }

    public String getName(){
        return name;
    }

    public Node(){

    }
    public int getData(){
        return data;
    }

    public void setData(int data){
        this.data=data;
    }

    public Node getLeft(){
        return left;
    }

    public void setLeft(Node left){
        this.left=left;
    }

    public Node getRight(){
        return der;
    }

    public void setRight(Node Right){
        this.right=right;
    }

class main{
    public static void main(String[] args){
        BST b1=new BST();
        Node root=new Node(); 
/*Here the root is null, I think this causing the NullPointerException, but if a have a constructor with parameters it doesn't insert any name instead the one that I put in the parameter*/
        b1.insertNames(root, 0, "Roy", 0);
        b1.insertNames(root, 0, "Joseph", 0);
        b1.printInorder(root);
    }

}