Certified GKH Gardening Expert
Although these are called "bamboo" they are actually a species of Dracaena! With this being said, they have a different care than bamboo will.
They are very well adapted to being cramped up in a small container, and prefer to be cramped, but should you feel that you need to transplant, then you will want to choose a well draining soil and transplant as you would any plant.
Take the old plant out of the container, and hold it up to the top of the new container so that you can see how much soil that you need to put under it. After you fill the soil to where you need, then place the plant on the soil and fill in the sides up to match the level of the old containers shape. water in and let ALL extra water leave the container through the drainage holes. Add extra soil if needed. Some will compact down after watering.
This article will give you more information on the care of these: https://www.gardeningknowhow.com/houseplants/dracaena/dracaena-houseplant-care.htm