Q.Zamioculcas
can I use regular potting soil to re pot
and how can the plant be separated ?

Certified GKH Gardening Expert
These are best grown in cactus-type soils. These can be split, but it is best to wait until any other pups are rooted themselves before you split them. Otherwise I would leave them alone. If you have separate root systems, then they can be split similar to aloe. Here is an article for more information on their care: https://www.gardeningknowhow.com/houseplants/zz-plant/caring-for-zz-plant.htm