Step 1 : Create the console application
Step 2 : Add the AssurBox NuGet package
Step 3 : Go to the AssurBox web application and get your identity keys
Step 4 : Use the keys to get a token
Step 5 : Use the token to use the Api (list companies)
Step 6 : Create a contract termination request
Step 7 : Check for a response.

Get the code of this video here : https://github.com/AssurBox/Demo-Csharp-Api-Client/tree/master/Service%20provider%20-%20console%20application/SPConsoleApplication