When you use page builder for single portfolio on option, maybe you will see results in your page blank (not visible porfolio content or look different). before you start adding the porfolio, you need to go to elementor> settings> click check on the porfolio> Save change.
- look at the screenshot
Now you can click edit with elementor on your porfolio :
wait for a moment for your elementor, when elementor has set up, click add template
> click my template tab > insert "Rekam single porfolio" template :
your porfolio has set up, next you can edit single porfolo content by yourself with edit with elementor