MyFirstMAUI/MyFirstMauiApp/PageLayout/MainPage.xaml

<?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"
             xmlns:myApp="clr-namespace:PageLayout"
             x:Class="PageLayout.MainPage">

    <ScrollView>
        <myApp:ByGridLayout/>
    </ScrollView>

</ContentPage>