What problem is actually you are facing? @ana.fer
Quiet, is solved. The problem was that we did not know how to make aparecienran posts in the portfolio. We now know that they have to put the same labels that the portfolio.
I have same problem, how do you solved yours?
You have to make a category to select the entries you want to be in the portfolio and then in the template options in portfolio settings choose that category.
Kindly, follow these steps to get your gallery section there:
1) Just visit your Dashboard->Posts->Tags and create tag(s) say: gallery
2) Check whether you have configured a Feature Image for your posts, if not then, upload it.
3) Add the same tag(s) say: gallery which is created in above step with your desired categories to your post and update it..
4) Do this for your other posts and check save settings.
5) Now, visit Dashboard->Appearance->Customize->Portfolio Section Settings there, you will have to select the tag from the dropdown list and save the settings
In this way, you will get your gallery section on the home page.