Laravel DB Select Query

I'm learning Laravel 5. Need help with query and print in blade. I have one table with users info and one table with Steam info where I have user_id row. How can I build this query:

SELECT username FROM steam WHERE id = user_id;

user_id is logged user in session

@section('content')
    <h3>Update your profile</h3>
    <div class="row">
        <div class="col-lg-3">
              Here print username from DB
        </div>
    </div>
@stop

via Chebli Mohamed