Parent/Child relationship between Telerik Dropdownlist and kendo-form - telerik

Question

I've got a Telerik UI for ASP.NET Core DropDownList which displays a list retrieved via an API call. Below it I have a kendo-form, and my intention is to "bind" it to the dropdownlist, so that when a different selection is made, the form data changes to the parent's. I cannot for the life of me figure out how to manage this.
The code for the dropdown + form is:
<kendo-dropdownlist name="setlist"
datatextfield="Name"
datavaluefield="Id"
option-label="Select Sieve Set..."
height="300">
<datasource type="DataSourceTagHelperType.Ajax">
<transport>
<read url="/Admin/ManageSieves?handler=Read" data="forgeryToken" />
</transport>
</datasource>
</kendo-dropdownlist>
<kendo-form name="setform"
layout="grid"
form-data="#Model"
method="POST"
asp-controller="ManageSieves"
asp-action="Read">
<grid cols="1" gutter="20" />
<form-items>
<form-item field="Name">
<item-label text="Name" />
</form-item>
<form-item field="TagMapping_BedPressure">
<item-label text="Bed Pressure" />
</form-item>
<form-item field="TagMapping_BedPressureValve">
<item-label text="Bed Pressure Valve" />
</form-item>
<form-item field="TagMapping_FeedFlowRate">
<item-label text="Feed flow rate" />
</form-item>
<form-item field="TagMapping_FlowToEvap">
<item-label text="Flow to Evap" />
</form-item>
</form-items>
</kendo-form>
Really simple parent-child relationship, but I'm finding the Telerik documentation to be a little opaque.
There is no real controller, since this is a Razor page that simply returns the results of CRUD operations by calling an API.
public JsonResult OnPostRead([DataSourceRequest] DataSourceRequest request)
{
this.DoOnPosts();
return new JsonResult(sieveSetModels.ToDataSourceResult(request));
}
What I'd like to find is a way to refer to the Read operation in the kendo-form, then pass in as an argument the Id of the selected DropDownList item - and to somehow do this in the onchange event.
I'm pretty new to JavaScript, which may be holding me back. I'd appreciate any ideas. Thanks.