You can add a logo image to the site identity header in addition to having a text title and description.
You can see examples below of the header with and without a logo image.
Default header without logo image.
Header with logo image.
Where and how to add the logo image:
In WordPress Admin > Appearance > Site Identity> Change Logo.
The recommended size is 250 x 250 pixels.
I uploaded an image of size 1920 x 1080 and by default, the customizer is set to crop the image to square proportions. I dragged the crop rectangle to make it full size and the full image is displayed as the logo.
There is an option to display, or not, the site text title and tagline (description) under the logo. If you switch off the text, the header logo is displayed slightly at a slightly larger size.