Certified GKH Gardening Expert
If they came from a tree, then you will not want to use soil. An epiphytic Bromeliad will want to be put into an orchid potting mix with just a little compost mixed in at most. Cactus mix will also be a suitable soil substitute.
These articles will help you with general care of Bromeliads: https://www.gardeningknowhow.com/houseplants/bromeliad/growing-bromeliad-pups.htm