Certified GKH Gardening Expert
This article will help with the plant's care: https://www.gardeningknowhow.com/houseplants/snake-plant/snake-plant-care.htm
Yes, it should be in soil. Use a fast draining mix for cactus, and work it all around the roots. How often to water it is never the question you need to ask; the question should be how do I know when to water. The answer is When the plant is dry all the way to the bottom of the pot. Test it with a kebob skewer as if you were testing a cake. If your snake plant is in low light - barely enough light for you to read by - letting it dry completely is imperative. If it's in a little more light, you can allow the soil to be slightly damp when you water again. But if it's been growing well enough to have divided it several times, you must be watering it right.
I've had mine a few years and it is in a full pot of soil. I have only divided it once but have always replanted in soil. I only water it once every two weeks at the most and I live in a dry climate (North Dallas).