A censer is a vessel that is used to hold smoldering charcoal (from a fire or self-igniting disks) upon which one burns the herbs, resins, gums, etc that make up their incense.
Censers can take many forms, they can be large, elaborate swinging vessels hanging on three chains, similar to those used by the Catholic Church, they can be a metal dish upon a stand (like a tripod) or any fireproof vessel that is suitable for holding the smoldering charcoal.
Your choice of censer will come down to preference, tradition & the type of magick or rituals you’ll be using it for.
If you’re totally new to Wicca & Magick, incense sticks or cones will work just fine until you find the perfect censer for you.