In this article I will be talking about what you need to start developing for the full .NET Framework.
While following these steps will just about get you there to develop for .NET Core, you can actually use a much simpler setup if only targeting .NET Core.
For more info, on .NET Core head on over to this article. Have a browse around the site for all sorts of other information too.
Step 1 - Get some hardware
To do .NET development using the full .NET framework you are going to need a windows computer. Ideally something with decent specs and a bit of RAM. You will be spending a lot of time in GUI RAM heavy tools.
My current machine is an Acer Aspire S7 Ultrabook with an Intel Core i7 CPU, 8 Gigs RAM and a 256 SSD. You don't need something this powerful but I'd say an i5 with 8 Gigs of RAM is probably the minimum specs you want to run.
Step 2 - Install some software
You only really need to install one bit of software to start programming in .NET and that is Visual Studio. Visual Studio is an IDE that you will pretty much find yourself living in during most of your development.
At the time of writing, I am using Visual Studio 2015 Enterprise but you will get on just fine with the free Visual Studio Community Edition. You can download Visual Studio from here.
Optional Step 3
If you are wanting to also build websites using the popular ASP.NET framework you are also going to need to enable some windows features.
Go into you programs and features settings and enable Internet Information Services (aka IIS) as well as the ASP.NET framework.
Example of what I have enabled:
You will probably find yourself needing a database at some point or another. Generally speaking, you will probably be using Microsoft SQL Server although you could get on just as well with MYSQL or some other relational database technology.
Scott Hanselman has a great blog post on installing MS SQL Server as well as the Management Tools that will make your life a bit easier - both are free.
Comment below if you have any questions.