Beginner issue with blazor and c# code - running the app, which file to choose

### URL

https://dotnet.microsoft.com/en-us/learn/aspnet/blazor-tutorial/run

### Operating system

windows 11

### More information about your system

x64 win 11, fairly new vs.code install. First attempt with blazor

### Description

I am doing the tutorial and got to the start app and debug portion, and it is unclear which file to have selected when I try to start the app in debug. I tried the project folder and the json and the vscode asked if I needed a plaint text debuuger or a json debgger. I have been building fairly simple apps in c#, mostly with full vs for years and it took me a few tries to get this going.
A newbie defintely will get stuck.
I have used vs.code for python for a few years and I am just setting up a new desktop to make sure everythign works and saw this blazor demo and figure I might want to update some mvc web apps I have.

### dotnet --info

dotnet --info
.NET SDK:
Version: 9.0.306
Commit: cc9947ca66
Workload version: 9.0.300-manifests.87361a52
MSBuild version: 17.14.28+09c1be848

Runtime Environment:
OS Name: Windows
OS Version: 10.0.26100
OS Platform: Windows
RID: win-x64
Base Path: C:\Program Files\dotnet\sdk\9.0.306\

.NET workloads installed:
There are no installed workloads to display.
Configured to use loose manifests when installing new manifests.

Host:
Version: 9.0.10
Architecture: x64
Commit: e1f19886fe

.NET SDKs installed:
9.0.306 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 9.0.10 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 6.0.36 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.11 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.10 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 6.0.36 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.11 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
x86 [C:\Program Files (x86)\dotnet]
registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation]

Environment variables:
Not set

global.json file:
Not found

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