Given you want to do it in .NET Framework, you possibly can try below:
1. Add a reference to Microsoft.VisualBasic
2. Refer namespace Microsoft.VisualBasic.Interaction (InputBox is in this namespace)
3. Try something like below:
string input = Interaction.InputBox("Prompt", "Title", "Default", x_coordinate, y_coordinate);
As I was shared, this might not work in .NET Core though.