Filament Template

PageTemplates_Faq.php

<?php

namespace App\Filament\PageTemplates;

use Filament\Forms\Components\Repeater;
use Filament\Forms\Components\RichEditor;
use Filament\Forms\Components\TextInput;

final class Faq
{
    public static function title()
    {
        return 'FAQ';
    }

    public static function schema()
    {
        return [
            TextInput::make('title'),
            Repeater::make('faq')->label('FAQ')->schema([
                TextInput::make('title'),
                    Repeater::make('items')->schema([
                        TextInput::make( 'title'),
                        RichEditor::make('content')
                    ])
                ])
        ];
    }
}

Resources_PageResource.php

<?php

namespace App\Filament\Resources;

use App\Filament\Resources\PageResource\Pages;
use App\Models\Page;
use Filament\Forms;
use Filament\Resources\Form;
use Filament\Resources\Resource;
use Filament\Resources\Table;
use Filament\Tables;
use Illuminate\Filesystem\Filesystem;
use Illuminate\Support\Collection;
use Illuminate\Support\Str;
use SplFileInfo;

class PageResource extends Resource
{
    protected static ?string $model = Page::class;

    protected static ?string $navigationIcon = 'heroicon-o-document-text';

    protected static ?string $navigationGroup = 'Inhalte';

    protected static ?string $label = 'Seite';

    protected static ?string $pluralLabel = 'Seiten';

    public static function form(Form $form): Form
    {
        return $form
            ->schema([
                Forms\Components\Select::make('template')
                    ->reactive()
                    ->options(static::getTemplates()),

                ...static::getTemplateSchemas(),
            ]);
    }

    public static function getTemplates(): Collection
    {
        return static::getTemplateClasses()->mapWithKeys(fn ($class) => [$class => $class::title()]);
    }

    public static function getTemplateClasses(): Collection
    {
        $filesystem = app(Filesystem::class);

        return collect($filesystem->allFiles(app_path('Filament/PageTemplates')))
            ->map(function (SplFileInfo $file): string {
                return (string) Str::of('App\\Filament\\PageTemplates')
                    ->append('\\', $file->getRelativePathname())
                    ->replace(['/', '.php'], ['\\', '']);
            });
    }

    public static function getTemplateSchemas(): array
    {
        return static::getTemplateClasses()
            ->map(fn ($class) =>
                Forms\Components\Group::make($class::schema())
                    ->columnSpan(2)
                    ->afterStateHydrated(fn ($component, $state) => $component->getChildComponentContainer()->fill($state))
                    ->statePath('temp_content.' . static::getTemplateName($class))
                    ->visible(fn ($get) => $get('template') === $class)
            )
            ->toArray();
    }

    public static function getTemplateName($class)
    {
        return Str::of($class)->afterLast('\\')->snake()->toString();
    }

    public static function table(Table $table): Table
    {
        return $table
            ->columns([
                Tables\Columns\TextColumn::make('slug')->sortable(),
                Tables\Columns\TextColumn::make('title')->sortable(),
                Tables\Columns\TextColumn::make('updated_at')->dateTime('d.m.Y, H:i')->sortable(),
            ])
            ->filters([
                //
            ]);
    }

    public static function getRelations(): array
    {
        return [
            //
        ];
    }

    public static function getPages(): array
    {
        return [
            'index' => Pages\ListPages::route('/'),
            'create' => Pages\CreatePage::route('/create'),
            'edit' => Pages\EditPage::route('/{record}/edit'),
        ];
    }
}

Resources_PageResource_EditPage.php

<?php

namespace App\Filament\Resources\PageResource\Pages;

use App\Filament\Resources\PageResource;
use Filament\Resources\Pages\EditRecord;
use Illuminate\Support\Str;

class EditPage extends EditRecord
{
    protected static string $resource = PageResource::class;


    protected function mutateFormDataBeforeFill(array $data): array
    {
        $data['temp_content'][static::getTemplateName($data['template'])] = $data['content'];
        unset($data['content']);

        return $data;
    }

    protected function mutateFormDataBeforeSave(array $data): array
    {
        $data['content'] = $data['temp_content'][static::getTemplateName($data['template'])];
        unset($data['temp_content']);

        return $data;
    }

    public static function getTemplateName($class): string
    {
        return Str::of($class)->afterLast('\\')->snake()->toString();
    }
}

Amazing. Thanks.
For multiple options: ->visible(fn ($get) => in_array($class, $get('template')))