can Someone explain how can i make one field in Drupal 8 that can contain multiple fields in it... I am not allowed to use Paragraph module. I want to make it full programmatically, By the way i know how to make simple field in Drupal 8 but don't know how to set schema or form form dynamic field that can have multiple fields in it. For Example when we want to add some field in user or in node, we go to ~/fields/add-field and then select the field type, after in the field setting i want to have one form element that says add filed and the type of the field. and after saving setting, i will generate the field widget and formater depending on the field type selection that i made before.
Is there a solution for this problem (only programmatically)?