First, you'll want to make sure that you have some page sections added to your site

To add/edit/reorder pages section click on 'Sections' to view your added section. Click on 'Add Section' if you'd like to add a new one

Once you've added your page sections, scroll up to the top of your site and hover over the area where the link would be and click 'Edit Navigation'

Click 'Add Navigation Links' or click on an existing one to edit it

Select 'Section' if you want to link to the page section(s) you've added. or 'External' if you want to link to an external website URL.

Give your link a title (this can be whatever you want and does not have to match the name of the page section).

You can drag to reorder these item in your navigation if needed

Click 'Save' and you are done!