add migration

db/migrate/20230703103209_create_default_favorites.rb

+class CreateDefaultFavorites < ActiveRecord::Migration[7.0]
+  def up
+    User.not_visitor.not_contributor.not_author.not_teacher.not_program_manager.each do |user|
+      return if user.favorites.any?
+      return if user.university.websites.many?
+      user.favorites.create(about: user.university.websites.first)
+    end
+  end
+end