Is it possible to group where clauses in Laravel?

I want to group item based on ORDER NO Where sales made by login User

 $sales = KotOrder::orderBy('id','DESC')
 ->where('prepared_by', Auth::user()->id)
 ->get();
return view('settups.restaurant.pos.report', \compact('sales'));

And I tried this

    $sales = KotOrder::orderBy('id','DESC')
     ->groupBy('qrtxt')
     ->where('prepared_by', Auth::user()->id)
     ->get();
    return view('settups.restaurant.pos.report', \compact('sales'));

It gives out error