For selecting list of name you can use Label Selector widget and you can add new object using Label Selector.
Hey Alvaro Riaño ,
you can do that through the below :
1- create one entity call it names and for example one attribute call it name.
2- link your entity with name entity (1-*) and the owner of the association will be your entity not the names entity
3-at the page add reference selector widget ,And the name entity will appears to select the name attribute ,Now you can select the names from pre-defined list
5- and for the names entity generate overview page and you can add new and remove from the list .
Hope my answer meet your requirement and resolve your issue .