This follow the lunar structure code.

First create folder call Pages and Components inside App\Http\Livewire it will become something like this.

App\Http\Livewire\Components App\Http\Livewire\Pages

Moving on. we will create new Page call Foo

1. Create livewire component call FooIndex inside Pages

<?php

namespace App\Http\Livewire\Pages\Foo;

use Livewire\Component;

class FooIndex extends Component
{
    public function render()
    {
        // in this example iam using default lunar layout.
        // if you want to use your own layout it's up to you
        return view('livewire.pages.foo.index')
            ->layout('adminhub::layouts.app'); 
    }
}

2. Create livewire view call index.blade.php in resources/views/livewire/pages/foo/index.blade.php

<div>
    This is from foo index
</div>

3. Add foo routes

Note: Pages only for routes.

Route::group([], function () {
    Route::get('foo', \App\Http\Livewire\Pages\FooIndex::class)->name('hub.foo.index');
});

4. Add custom menu inside AppServiceProvider. refrence https://docs.lunarphp.io/extending/admin-hub.html#adding-to-menus

$slot = Menu::slot('sidebar');

$slot->addItem(function ($item) {
    $item->name('Foo')->handle('hub.foo')
        ->route('hub.foo.index')
        ->icon('foo');
});

First create FooIndex inside Pages

App\Http\Livewire\Pages\FooIndex

<?php

namespace App\Http\Livewire\Pages\FooIndex;

use Livewire\Component;

class FooIndex extends Component
{
  public function render()
  {
    return view('livewire.pages.foo.index')
      ->layout('adminhub::layouts.app');
  }
}

Inside resources/views/livewire/pages/foo/index.blade.php

<div>
    @livewire('hub.components.settings.application.index')
</div>