the logo on your current site has a lot of whitespace around it – if you can crop the image so that is removed then upload that new image as the logo. Once done you just need to:
1. Set the Customizer > Layout > Primary Navigation –> Menu Item height to match the height of the logo.
2. Reduce the Customizer > Layout > Header –> Top and bottom padding.
there are several ways a logo can be added and therefore the answer will be dependent on your site setup.
If you can raise a new topic, where you can share a link to your site we can then advise.