how to make the first letter big in word javascript code example

Example 1: javascript uppercase first character of each word

const uppercaseWords = str => str.replace(/^(.)|\s+(.)/g, c => c.toUpperCase());

// Example
uppercaseWords('hello world');      // 'Hello World'

Example 2: javascript capitalize

myString = 'the quick green alligator...';
myString.replace(/^\w/, (c) => c.toUpperCase());

myString = '    the quick green alligator...';
myString.trim().replace(/^\w/, (c) => c.toUpperCase());