Or in your site front page, in the admin bar find Edit Page ( Back-end Editor ) or Edit with WPBakery Page Builder ( Front-end Editor )
For changing size and margin, go to Theme Options > Header > Header > Logo element
For disabling slider or changing it with other title type
Example Breadcrumbs or Title, Go to Page Edit > Page Settings > Title Type
For overall website page title type go to Theme Options > Title & Bredcrumbs
Instead Quick Contact also you can create any page and assign it.
In widgets find Footer 1 to Footer 4 sidebar area sections and edit them.
For changing background color of Footer, Go to Theme Options > Footer > Footer Widgets > Row Container StyleKit
This element has -130px margin from the top and you can find it in Container stylekit.
For changing the background color you can go to Inner Columns Settings > Design Options Tab.
Below image you can edit Title and Text element.
This Grid set to Crousel and you can find the Carousel’s settings under the Carousel tab in the edit panel.
This element has -80px margin from top and you can find it in Container stylekit of this element.
This element has -80px margin from top and you can find it in Container stylekit of this element.
For editing menu navigation settings go to Theme Options > Header > Header bottom bar > Menu Element
And for styling menus go to Theme Options > Header > Header bottom bar > Menu Styles of this Row