How to select dotnet version

### Describe the bug

How do I select the dotnet version when I create the project, the default is 6.0

### Steps to reproduce

Create Project
<TargetFramework>net6.0</TargetFramework>

### Expected behaviour

<TargetFramework>net8.0</TargetFramework>

### Template

Api、GrapgQL

### .NET Boxed Version

7.4.0

### Visual Studio Version

Visual Studio 2022

### .NET Version

.Net8