Concatenate list field

I have a Look Up column that brings me all related products from another table.
I need to concatenate all the texts.
For example:
An Order has 3 products:
Pears, Apples and Bananas in an Order Items table.
From the table Order, in a relation column I bring all the items of each Order.
I need to merge all those items into a single text field:

The Template column doesn’t seem to allow it.
How do I do it?

It should be easy with template, as long items are in the same row

Hola @Alfredo_Pou

Make sure your relation is a multiple relation and create a joined list column to that relation.
You’ll get what you need.