A creed is a formal profession of religious belief. Buddhism doesn’t require that you believe anything. The Buddha said that we shouldn’t take anything he said on faith, but that we should investigate his words and come to our own conclusions. You can be a Buddhist without making any professions at all. Most people who become interested in and then dedicated to following the path of Dharma, however, begin by taking refuge. This is just a matter of telling your teacher or a lama or a nun that you intend to take refuge in the Buddha, the Dharma (the path) and the Sangha (the community). Some people like to have this be a formal ceremony and others do not.