To install Visual Studio Code we need to open a terminal window

First install the key

 sudo rpm --import https://packages.microsoft.com/keys/microsoft.asc

Install the repository

sudo sh -c 'echo -e "[code]\nname=Visual Studio Code\nbaseurl=https://packages.microsoft.com/yumrepos/vscode\nenabled=1\ngpgcheck=1\ngpgkey=https://packages.microsoft.com/keys/microsoft.asc" > /etc/yum.repos.d/vscode.repo'

Update the package cache

 sudo dnf check-update

Then install code

  sudo dnf install code

Now that VS code is installed

Lets install the .net core 3.1 sdk

First get the key and repo

  sudo rpm --import https://packages.microsoft.com/keys/microsoft.asc

  sudo wget -O /etc/yum.repos.d/microsoft-prod.repo https://packages.microsoft.com/config/fedora/31/prod.repo

Now we can install .net core 3.1

  sudo dnf install dotnet-sdk-3.1

Make sure in Visual Studio code you install the C# extension by Microsoft