Excel: I want to split my data into a new row

I need some help in sorting my data. As in the image, the original file look like top image and I want to split the size into a new row below for all items as in the bottom image.

The file contain multiple column that look like this. All content are separated with comma. I want to split these data into a new row under the original item for 1000 items per page.

I am using Excel 2016 .