To add Portfolio Items to Dropdow in Main Navigation, you can follow these.
#1. First, find Portfolio item url.
You can hover on each portfolio item > click 3 dots > Settings

See URL Slug

In my example, we will have some items with url
- /work/netflix
- /work/coca-cola
- /work/nokia
- /work/fpt
#2. Click Plus icon > Choose Dropdown

#3. Name it Portfolio with URL /portfolio. You can also use any other names: Work, Project,…

#4. Click ADD Page > Choose Link

#5. Enter Title + URL (you got in step #1)

You will have

#6. Result

#7. Note
You won’t click “Portfolio” title. To make this clickable to Portfolio Page. You can follow these.
#7.1. First, hover on Portfolio > Click Gear icon

#7.2. See URL Slug. In my example, it is: /work

#7.3. Use this code to Code Injection > Footer
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.0/jquery.min.js"></script>
<script>
$(document).ready(function() {
$('a.header-nav-folder-title[href="/portfolio"]').click(function() {
var link = $(this).text(),
href = "/work";
window.location.href=href;
});
});
</script>
