wrote you already be mail. Please follow these steps:
Go to WordPress admin -> Portfolio -> Add New. Now create a single portfolio entry, Insert a title, then the text and upload a featured image ( it’s important for the preview ).
Create a new Page (WordPress admin -> Pages -> Add New ), please insert a title, for example “Portfolio”, then choose one of the portfolio templates as template, for example “Portfolio Grid”. Publish the page, then add this page to the Menu and all is done. This page is a “summary” for your portfolio entries, like this one here:
Normally it’s really very easy to create new portfolio entries and display them in a page…