How do I extract data using APIs to load into SQL Server using ASP.NET?

Answer 1

If I understand the question correctly, you have a source and a target. Your target is a SQL database. You didn't say what your source is, but assuming it's a database you can do the following...

Use the service pattern for both the source and destination. Then in your API Controller you just call the service of the source then pass that data onto the service of your destination.