No. They are very different. A Post is a tiny metal building rod that is placed within a broken tooth to help build back the tooth and retain filling material when there is limited healthy tooth.
In contrast, an Implant is a biocompatible material, in the form of a post, that is surgically implanted into the gum and bone where the natural tooth was lost. Once healed, a ceramic crown, that looks like a natural tooth, can be attached to this implant.