Are you still looking for answer to this question?

The bubble wrap can be bought from stationary supplier, one roll is almost 1m tall and 2-3feet in width. If you are not consuming that much of bubble wrap, you can buy smaller quantities from ACE hardware and Daiso, where they sell in packs.

The bubble wraps are only intended to fill up voids in your packaging space. Ideally, you would not want too much voids. A 6cm gap between content to wall is recommended.

There are other materials to fill up voids too, for example, foam, air bags, pellets, or even crumpled papers.

Depending on the content you ship, some may require special care (e.g.: fragile), do use "special handling labels" on your box.

To find the right size for your box, you can order packaging supplies via myDHL+ account. Ship>Order Supplies.

You can find the general guidance document here:

Packing Guide

From where to where?
Parcel weight?

Around RM18. Checked at easyparcel.com