Please choose a different page template. I can see you are using Blank – No Container | No Header, No Footer. The header holds the navigation and since your current template has no header, there’s no navigation.
Thanks for writing in! Please edit your page and change your page template. You need to change it to Blank – No Container | Header, Footer page templates. To learn more about page templates, please check out our knowledge base: https://community.theme.co/kb/page-templates/