upload image in laravel 7 ErrorException Array to string conversion

i use 3 array to store in table courses. please help me to save array in string or save array in database...my problem with array:

1- i cant store and save image in database

2-i cant save array outcomes and requirements in database

       <div class="col-md-10"><input type="file" class="form-control" name="images" id="images" ></div>
//and this 
       <input type="text" class="form-control" name="outcomes[]" id="outcomes">
//or this
       <input type="text" class="form-control" name="requirements[]" id="requirements">

my store function call:

   public function store(CourseRequest $request)
{
    $imageUrl = $this->upload2Images($request->file('images'));
    auth()->user()->course()->create( $request->except(['_token','files']),['images'=>$imageUrl]);
    return redirect(route('courses.index'));
}

and uploadImages is

public function upload2Images($file)
    {
        $year = Carbon::now()->year;
        $month = Carbon::now()->month;
        $imagePath = "upload/images/{$year}/{$month}/";
        $filename = $file->getClientOriginalName();
        $file = $file->move(public_path($imagePath), $filename);
        $url['images'] = "upload/images/{$year}/{$month}/$filename";
        return $url;
    }

via Chebli Mohamed