I updated this site from .NET 6 to .NET 7.  As with the change from .NET 5 to .NET 6, this was quite easy: I just had to change the target framework in the project's csproj file from 

<TargetFramework>net6.0</TargetFramework>

to 

<TargetFramework>net7.0</TargetFramework>

However, for some reason, although I asked in the publish profile from Visual Studio 2022 for it to publish using .NET 7, this didn't happen: I had to increase the setting by hand (Configuration, General settings) in the Azure portal for the app service to use .NET 7.

This was for the app service.  There is also an Azure function (which updates an Azure Table every day so that the data that is used to create the category and tag clouds is kept up to date).  It is not so clear that the function should be upgraded from .NET 6 to .NET 7 because .NET 7 functions are meant to run using the .NET Isolated Worker model, which could be a more significant change than that just upgrading the target framework for an app service. 

.