Bengali with english in same page using dompdf support

I want to print pdf using bengali(Unicode) and English in same page. But got "???? ????" for bengali(unicode). Here is my code.

<!DOCTYPE html>
<html>    
<head>
<meta http-equiv="Content-Type" content="text/html;"/>
  <meta charset="UTF-8">
    <title>Title</title>
    <style> 
    @font-face {
    font-family: "kalpurush";
    font-style: normal;
    font-weight: normal;
    src: url(kalpurush.ttf) format('truetype');
}
* {
    font-family: "kalpurush";
}

</style>
</head>
<body>
<table class="table table-responsive" id="questions-table">
    <thead>
        <th>#</th>
        <th>Subject</th>
        <th>Difficulty</th>
        <th>Question</th>
        <th>Marks</th>
        <th>Status</th>        
    </thead>
    <tbody>

    @foreach($questions as $question)
        <tr>
        <td>{{Form::checkbox('id', $question->id)}}</td>
            <td>{!! $question->subject->name !!}</td>
            <td>
            @if($question->difficulty == '1')Easy
            @elseif($question->difficulty == '2')Medium
            @elseif($question->difficulty == '3')Hard
            @endif
            </td>
            <td>{!! $question->question !!}</td>
            <td>{!! $question->marks !!}</td>
            <td>{!! $question->status !!}</td>            
        </tr>
    @endforeach
    
    </tbody>
</table>
</body>
</html>

And here is how I am printing to PDF >

$question = \App\question::get();
view()->share('questions',$question);
$pdf = PDF::loadView('pdf.question');   
return $pdf->download('abc.pdf');
//return view('pdf.question')->with('questions',$question);
})->name('test');

Route::any('/test2', function(Request $request){
$pdf = PDF::loadView('pdf.question');   
return $pdf->download('htmltopdfview');

Here is the link for test file which it creates

https://ufile.io/1o6nj

Help needed. Thanks.

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