After choosing a theme you’ll want to create a menu at the top of your site with links to each of the important pages.
The way I like to do this is by using the WordPress Customizer. Here you’ll be able to create new pages and add them to your menu without having to click through a bunch of screens.
You’ll find the Customizer under the Appearance menu in the Dashboard.
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There you can click on the Menus section.
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Create a new menu.
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Give it a name.
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Scroll down and hit the Next button at the bottom.
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Click the Add Items button.
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Then start adding Pages to your menu either by creating new ones or adding existing ones.
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This is the fastest way I have found to create new pages and add them to a menu. There won’t be any content in the pages, but they will be good placeholders for when you’re ready.
Once you’re done then hit the Publish button at the top.
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And then you can close the Customizer with the X in the top left.
This will take you back to the Dashboard where you can view all of your new pages.
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There you can edit your pages with the WordPress Block Editor, Classic Editor or with your favorite page builder plugin.