C# app stop executing and release reosurces

Question

I have a C# 2008 windows/console application that I need to support that never seems to stop running. This application
seems to not release resources also. This application does not close connections also.

Thus can you show me in code, tell me, and/or point me to a reference that will answer the following questions:
1. How can I force a program to stop running?
2. How can I have the application release resources?
3. How can I have the appliction close connections?
4. Of the steps listed above, can you tell me the order of how these ending operations should occur?