Добавил новую страничку

MobailApp.csproj

@@ -62,4 +62,10 @@
 		<PackageReference Include="Microsoft.Extensions.Logging.Debug" Version="8.0.0" />
 	</ItemGroup>
 
+	<ItemGroup>
+	  <MauiXaml Update="NewPage1.xaml">
+	    <Generator>MSBuild:Compile</Generator>
+	  </MauiXaml>
+	</ItemGroup>
+
 </Project>

MobailApp.csproj.user

@@ -6,6 +6,11 @@
     <ActiveDebugProfile>Windows Machine</ActiveDebugProfile>
   </PropertyGroup>
   <ItemGroup>
+    <MauiXaml Update="NewPage1.xaml">
+      <SubType>Designer</SubType>
+    </MauiXaml>
+  </ItemGroup>
+  <ItemGroup>
     <None Update="App.xaml">
       <SubType>Designer</SubType>
     </None>

NewPage1.xaml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             x:Class="MobailApp.NewPage1"
+             Title="NewPage1">
+    <VerticalStackLayout>
+        <Label 
+            Text="Welcome to .NET MAUI!"
+            VerticalOptions="Center" 
+            HorizontalOptions="Center" />
+    </VerticalStackLayout>
+</ContentPage>

NewPage1.xaml.cs

@@ -0,0 +1,9 @@
+namespace MobailApp;
+
+public partial class NewPage1 : ContentPage
+{
+	public NewPage1()
+	{
+		InitializeComponent();
+	}
+}