You need to understand a couple of things first:
ASP.NET is not a Windows Application, it is a Web Application. If you want a Windows Application you will need to use WinForms, WPF, or something along those lines.
As far as converters go, a google search on "vb6 to C# converter" or something along those lines should lead you to what is available out there. There is at least this one article here on CP that you may find helpful as well: VB6 C# VB Code Converter