If you don't have to use the new api in the Android version 34.0, the easiest way to update your app to android version 34 is setting the target sdk in the AndoridManifest.xml. Just add the following code in the AndoridManifest.xml.
<uses-sdk android:targetSdkVersion="34" />In addition, the .Net 7 is obsolete. So if you want to upgrade your maui project from .net 7 to .net 8, you can change the csproj file as the following code after installing .NET 8 and the .NET MAUI workload.
<PropertyGroup> <TargetFrameworks>net8.0-android;net8.0-ios;net8.0-maccatalyst</TargetFrameworks> <TargetFrameworks Condition="$([MSBuild]::IsOSPlatform('windows'))">$(TargetFrameworks);net8.0-windows10.0.19041.0</TargetFrameworks>The .net 8.0 maui project target Android version 34 defaultly. For more information, you can refer to Upgrading .NET MAUI from .NET 7 to .NET 8.