How to run a Javascript function with certain delay?

Using setTimeout we can invoke a function with delay. Following code shows you how to do that.

setTimeout(() => your_function(), 1000);

First parameter for setTimeout is a function and the second parameter is time in milliseconds.
Following is a full example that demonstrates setTimeout

function hello()
{
  console.log("Hello, World!");
  console.log('after:' + new Date());
}

console.log('before:' + new Date());
setTimeout(() => hello(), 1000);

Output:

before:Mon Jul 06 2020 14:32:05 GMT+0000
Hello, World!
after:Mon Jul 06 2020 14:32:06 GMT+0000

You can run this and see yourself here https://onecompiler.com/javascript/3vy55pdma