how to get the first 3 letters of a string in javascript code example

Example 1: javascript get first 10 characters of string

var str = "Hello world That is reallly neat!";
var res = str.substring(0, 5);//get first 5 chars

Example 2: js get first 3 characters of string

const string = "0123456789";
console.log(string.slice(0, 2)); // "01"
console.log(string.slice(0, 8)); // "01234567"
console.log(string.slice(3, 7)); // "3456"

Example 3: str.substring if 2 letters

public String firstTwo(String str) {
    return str.length() < 2 ? str : str.substring(0, 2);
}