Modifying header back end

Hi. I need to modify header in my child theme and add few things (such as search box, few custom icons) to header to have them in the same section as logo, above the horizontal menu bar, next to logo.

How to do it and how to do that while running network sites using the same theme within the same wp installation? How to embed my code and where to paste it?

Thanks for any help and answers.

• This topic was modified 4 years, 6 months ago by pprzemyslaw.