Android internet connection related problems? We can USB tether and use android internet connection on PC but How to achieve following:
1. How to use pc internet connection on android device using USB cable on Windows machine?

I can use my android service provides internet connection to turn on WiFi hotspot but I stuck with following question:
2. Can my device access internet using WiFi and at same time can we convert it into WiFi hotspot? If yes How to do that? If not why it's not possible?
XDA developer capslock66 has developed a reverse tethering tool which is the simplest yet (and hopefully in future too). Only requirement is a rooted phone. You can download it from here-
Android reverse tethering via usb

It comes as a zip file with all the adb files and dependencies. Once you open the application, it will do all the settings on your phone automatically for USB data tunneling. And most importantly, the good thing is it now works with any app including Google Play/Market too. Google play earlier needed a WiFi, but now, it works with a reverse tethered connection too.