After you install the KWizCom modern apps in your site, you can start using the activated features in lists and libraries in the site.
In the list/library's toolbar, click the "KWizCom Apps" button to open the KWizCom list-level apps management page:

In the KWizCom Apps settings page you will see all the available KWizCom modern apps for this list:
To configure any of the apps' settings, click its gear icon
. COMMENT:
By default, the KWizCom Forms display mode is set to Off. This means that by default you will see the out-of-the-box SharePoint list forms, and that's why you will see the message at the top of the KWizCom Apps settings page:
To activate the KWizCom Forms feature in your list you should click the "KWizCom Forms Display Mode" button:
Now select one of the available display modes other than "Off":