1. First create a logo with png format.
  2. Then, go to the Favicon Icon Generator tool, click on Choose file, click on Create Favicon button and then download the file.
  3. Extract the downloaded zip file and upload all the images to GitHub page. [ don't rename the images.]
  4. Then download the three files [File 1, File 2, File 3] and also upload to GitHub page.
Later we will see how you can send notifications to the users. How users can install your website as an app.