Creating a control that looks like a combobox, but instead shows a Form. VB.NET, Windows Form, in framework CORE 6

I want to build a control named ucRichDropDown. It should look like a regular Combobox, but it should only show a Form. It should be built as a Windows Form control, in VB.NET, Framework CORE 6. It should be able to work as a user control, and it must also be work in a DataGridView as well.

The full requirements are attached in the PDF file.