Navigate to Appearance > Customize > Site Identity.
Set your site title and tagline. The tagline only displays in a browser tab an not on the site itself.
Use the select logo button to upload your logo. In order for your logo to line up correctly, I recommend uploading an image size of 100px height and max 480px width.
Upload your favicon under the site icon area. Suggested size for your favicon is 512 x 512px.