Example of how to work with MVVM pattern using the MVVMCoffee nuget package - http://julianocustodio.com/mvvmcoffee

MainPage.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:d="http://xamarin.com/schemas/2014/forms/design"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             mc:Ignorable="d"
             x:Class="Sample.MainPage"
             Title="{Binding TitlePage}">

    <StackLayout Margin="20" VerticalOptions="Center">
        <Label Text="Examples of using MVVMCoffee plugin."
               HorizontalTextAlignment="Center"/>

        <Button Text="PushAsync to Form" BackgroundColor="#F3F3F3"
                Command="{Binding PushAsyncToFormCommand}"/>
        <Button Text="SetRootAsync" BackgroundColor="#F3F3F3"
                Command="{Binding SetRootFormCommand}"/>
    </StackLayout>

</ContentPage>