To begin, navigate to the Toolbar > Edit with Elementor > Header Dark







Or go to Templates > Theme Builder > Transparent Header > Edit with Elementor. Control the layout, conditions, rules and styles of the header template.






Please check these guides for further information:

Create Headers Using Elementor

Guide to Vamtam Elementor Builder




3. How to edit the logo image


You can edit the column and the Site Logo styles:


https://docs.elementor.com/article/368-column-overview

https://docs.elementor.com/article/453-site-logo-widget





To set the logo size, visit the Style section:





You can edit the Logo image, Site title and Tagline in Customize > Site identity:




You can check this guide for more details: Vamtam Elementor Themes: How to edit the Logo image, Site Title and Tagline?