Hello @nolansanjunior,
The feature to upload multiple logos is not a theme default feature in the Clean Journal theme. However, if you have some knowledge on WordPress Theme / Code handling, you can achieve the feature with customizing the code via child theme approach.
As the theme uses clean_journal_header_right()
function to display the right search form in the header you can customize the function via child theme’s functions.php file. You will also need to create additional upload field for the 2nd logo image or Use static image URL in the function output.
Also, for future reference, you can also choose to post your queries in the theme’s official support forum for dedicated and swift support at :
https://catchthemes.com/support-forum/forum/clean-journal-free/
Hope this helps,
Best Regards !!