how to get only items has avg rate equal value in one query laravel?

i want get only items has avg rate equal [3,5] // Example

when write in model

public function rate()
{
        return $this->hasMany('App\Models\Rate', 'fk_service')->avg(rate);
}

get error Call to a member function addEagerConstraints() on string

when remove "->avg(rate)" get all data but i want only average rate

when write in model

public function rate()
{
    return $this->hasMany('App\Models\Rate', 'fk_service');
}

// and in controller

$engravings = Engraving::where('engravings.status', 1);
if(!empty($request->rate)){
    $engravings->whereHas('rate', function($query) use ($request){
        // Code use WhereIn How To do it
    });
}

$engravings = $engravings->get();

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