If you want to add a button in your Header, except for the 2 menus layout, you can use the Menu Text Element under Theme Options > Theme & Header Options.

Let’s see the available ways depending on your builder.

WPBakery Page Builder

First of all, you can create any button that you want on a test page.
Then copy only the button shortcode (not the row, column shortcode) from Classic Mode – Text

Now, enable Menu Elements and select the Text Element on Menu Elements Options.

Below, place the copied shortcode under Theme Options > Header Options in Header Text Element – Text.

That’s it!

Alternatively, you can also use the following button shortcode instead of creating a new button.

<a class="grve-btn grve-round grve-bg-primary-1 grve-border-primary-1 grve-bg-hover-white grve-border-hover-white grve-text-white grve-text-hover-dark-grey grve-btn-medium grve-fullwidth-btn" href="#"> Purchase Impeka Theme </a>

Elementor

If you’re using Elementor you can use the above button shortcode.

So, you enable Menu Elements and select the Text Element on Menu Elements Options. Then add the button shortcode and save changes.

Gutenberg

In Gutenberg, you can use the same button shortcode or create a button block and copy the shortcode from Classic Editor.
Then follow the same way. You will need to enable Menu Elements and select the Text Element on Menu Elements Options. Then add the button shortcode and save changes.

Responsive Header

If you want this button on the Responsive Header too. You should enable Text Element and add the button shortcode under Theme Options > Theme & Header Options > Responsive Options.