How can I have multiple instances of a column that itself holds a foreign key reference?

Question

I am new to Visual Studio so to start learning it I first of all downloaded a sample available at https://code.msdn.microsoft.com/ADPNET-Entity-Framework-2d1160cb and started working around it. Since I have fairly good knowledge of VB6 and SQL it did
not take much time for me to understand the whole pattern the sample is based on. Had Microsoft given a detail explanation or a walk through of the sample it would have been much easier to understand the basics. However, I somehow managed to work around it
and have build a small desktop application in wpf using Entity Framework and MVVM. But a point has come where I have got completely stuck up finding no way out. The problem is as under:
I have two tables. 1 Advocate and 2 Party. Table Advocate would contain names of advocates and would have a primary key. Similarly Party would have names and their respective primary keys.
Then I have another two tables 1. Case and 2 CaseDetail. Table Case would simply hold three columns: 1. CaseId 2. CaseNo and 3. Year. Table CaseDetail would have CaseDetailId as a primary key the CaseId as a Foreign Key. Now what I need is that a particular
case could have multiple advocates and multiple petitioners. So the table CaseDetail would have two columns to hold advocateId and PartyId as a Foreign Keys. 
If you look at the sample referred above you would not find how to deal with such a case. When I follow the pattern of the sample I get host of design time and runtime errors. 
Therefore, please suggest what strategy should be adopted in a scenario described above while developing WPF application using Entity Framework and MVVM.

Answer 1

I am new to Visual Studio so to start learning it I first of all downloaded a sample available at https://code.msdn.microsoft.com/ADPNET-Entity-Framework-2d1160cb and started working around it. Since I have fairly good knowledge of VB6 and SQL it did not
take much time for me to understand the whole pattern the sample is based on. Had Microsoft given a detail explanation or a walk through of the sample it would have been much easier to understand the basics. However, I somehow managed to work around it and
have build a small desktop application in wpf using Entity Framework and MVVM. But a point has come where I have got completely stuck up finding no way out. The problem is as under:
I have two tables. 1 Advocate and 2 Party. Table Advocate would contain names of advocates and would have a primary key. Similarly Party would have names and their respective primary keys.
Then I have another two tables 1. Case and 2 CaseDetail. Table Case would simply hold three columns: 1. CaseId 2. CaseNo and 3. Year. Table CaseDetail would have CaseDetailId as a primary key the CaseId as a Foreign Key. Now what I need is that a particular
case could have multiple advocates and multiple petitioners. So the table CaseDetail would have two columns to hold advocateId and PartyId as a Foreign Keys. 
If you look at the sample referred above you would not find how to deal with such a case. When I follow the pattern of the sample I get host of design time and runtime errors. 
Therefore, please suggest what strategy should be adopted in a scenario described above while developing WPF application using Entity Framework and MVVM.