@simrin-- Celeriac (and celery too) are full of nutrition and vitamins but they can be kind of bland if they're not prepared correctly.
From my experience, celeriac is great in stews where it is simmered in flavorful sauces and broths. Celeriac root especially is good at absorbing flavors but keep in mind that the root cooks much faster than the stalks.
You should try an orange celeriac recipe which is basically celeriac root cooked in olive oil and orange juice. It's really delicious and the celeriac becomes sweet and very flavorful.