What are functional and non-functional requirements?

Functional requirements defines the behavior of a system.  
Non-functional requirements specify how the system should behave. in other words they specify the quality requirements and judge the behavior of a system.
Functional - Display a chart which shows the maximum number of products sold in a region.
Non-functional – The data presented in the chart must be updated every 5 minutes.

What is SRS and its USE

SRS establishes the basis for agreement between customers and contractors or suppliers on what the software product is expected to do, as well as what it is not expected to do.
An SRS minimizes the time and effort required by developers to achieve desired goals and also minimizes the development cost.
It sets the basis for software design, test, deployment, training etc.
It sets basis for software enhancement and maintenance.
It sets Basis for Project plans like Scheduling and Estimation.

Use case:
A use case is a list of steps, typically defining interactions between a role (known in UML as an "actor") and a system, to achieve a goal. The actor can be a human or an external system.

What is NuGet

NuGet is a Visual Studio extension.
NuGet helps us to install,update ,configure and remove third-party libraries and tools in Visual Studio.

Click here to download NuGet