How to use multiple controls in same page of app.xaml

<Application x:Class="New_Restaurant_Application.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:New_Restaurant_Application"
             StartupUri="MainWindow.xaml"
             xmlns:hc="https://handyorg.github.io/handycontrol">
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Light.xaml" />
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Defaults.xaml" />
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignColors;component/Themes/Recommended/Primary/MaterialDesignColor.BlueGrey.xaml" />
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <hc:ThemeResources/>
                <hc:Theme/>
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Application.Resources>
</Application>

<ResourceDictionary>
           <ResourceDictionary.MergedDictionaries>
               <hc:ThemeResources/>
               <hc:Theme/>
           </ResourceDictionary.MergedDictionaries>
       </ResourceDictionary>
   </Application.Resources>