In customize → site title
you can upload a svg here:
[image: 1693819121925-screenshot-2023-09-04-at-11.18.39.png]
if wordpress doesn't allow you to upload a svg, you could install a plugin like https://wordpress.org/plugins/svg-support/
you could also use type "html" here, and enter the text of the svg:
you can find the svg as text when you open your svg file with a texteditor
[image: 1693819192024-screenshot-2023-09-04-at-11.19.49.png]