1. Download .NET Core SDK

2. Register Microsoft key and feed

$ wget -qO- https://packages.microsoft.com/keys/microsoft.asc | gpg --dearmor > microsoft.asc.gpg
$ sudo mv microsoft.asc.gpg /etc/apt/trusted.gpg.d/
$ wget -q https://packages.microsoft.com/config/ubuntu/18.04/prod.list
$ sudo mv prod.list /etc/apt/sources.list.d/microsoft-prod.list
$ sudo chown root:root /etc/apt/trusted.gpg.d/microsoft.asc.gpg
$ sudo chown root:root /etc/apt/sources.list.d/microsoft-prod.list

3. Install

$ sudo apt-get update
$ sudo apt-get install apt-transport-https
$ sudo apt-get install dotnet-sdk-2.1

4. Check .NET Core SDK Version

$ dotnet --version
2.1.301

5. Create and Run Project

$ dotnet new console -o myApp
$ cd myApp
$ dotnet run
Hello World!