How to add a logo, site title and site icon
The branding of your website can be configured in Customize > Header > Site Identity. When you visit this section, you'll find options to change your site title, site description, logo, and site icon (favicon). You can also change the logo width here.
Use the Select logo field to upload your custom logo. It is suggested that you add a 250 X 250px logo. If you want to display only the logo (without the site title and description), you can uncheck the Display Site Title and Tagline option.
The Tagline is optional but it is recommended that you always fill your Site Title field.
Site icons are necessary for a complete website branding. A little further down you'll also find the Site Icon option.