The first component you will have to integrate in your project content is a "Form" component.
Expand Application -> NgxApp -> Pages -> Content.
Click it, then write "Form" in the palette. Drag & drop it into your Content.
Then, in this form, you can see that it exists two "FormItem" : Only one is needed here, so you can delete the second. In the "Controls" folder, disable or delete the alert -> you don't need it here.
Take your previously created sequence in your Back-end project "get_references_by_id" and drag & drop it into the "OnSubmit" field. (CTRL + drag & drop on Windows and OPTION + drag & drop on Mac).
Then expand Formitem -> TextInput. In the properties window, change Control name to "c8o_title". This will bind the input field name to the name of the sequence's variable.