Bruh... That quoted text says that it is a monotheistic religion. Please just learn the thing and don't die on the hill. They have a holy book (the guru granth sahib ji), together with a wider collection of religious and philosophical works (the bani). They have rituals and the like. Things like the 5 Ks. They believe in a singular deity (Ik Onkar) who is, according to Sikhism, the same deity that the Muslims call Allah. Onkar is the Punjabi symbol for Aum (A very important Hindu concept). The gurus (their leaders), are supposed to be god. The idea is that they are a reflection of God, likening God to the ocean and the gurus to a bucket that is filled by the ocean. Their holy book is the last and final guru and simultaneously god and leader/teacher.

Point of the above is I know what I am talking about. All of those are definitely religions with a belief in deities and afterlifes and holy books and miracles, etc...