remove first element from array and return the array minus the first element

var myarray = ["item 1", "item 2", "item 3", "item 4"];

//removes the first element of the array, and returns that element.
alert(myarray.shift());
//alerts "item 1"

//removes the last element of the array, and returns that element.
alert(myarray.pop());
//alerts "item 4"

1. How to remove the first array but return the array minus the first element
2. In my example i should get "item 2", "item 3", "item 4" when i remove the first element

This should remove the first element, and then you can return the remaining:

var myarray = ["item 1", "item 2", "item 3", "item 4"];
    
myarray.shift();
alert(myarray);

As others have suggested, you could also use slice(1);

var myarray = ["item 1", "item 2", "item 3", "item 4"];
  
alert(myarray.slice(1));

Why not use ES6?

 var myarray = ["item 1", "item 2", "item 3", "item 4"];
 const [, ...rest] = myarray;
 console.log(rest)

Try this

    var myarray = ["item 1", "item 2", "item 3", "item 4"];
    
    //removes the first element of the array, and returns that element apart from item 1.
    myarray.shift(); 
    console.log(myarray); 

This can be done in one line with lodash _.tail:

var arr = ["item 1", "item 2", "item 3", "item 4"];
console.log(_.tail(arr));

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.min.js"></script>

myarray.splice(1) will remove the first item from the array … and return the updated array (['item 2', 'item 3', 'item 4'] in your example).

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/splice

You can use array.slice(0,1) // First index is removed and array is returned.