The verb you choose depends upon the context in which it is used. These verbs are not interchangeable. To express knowledge or ignorance of a fact or information about something, use “saber.” To say that one is or is not acquainted with a person, a place, or an object, use conocer.
1. Conocer: Sé que George Washington fue el primer presidente.
2. Saber: Quiero saber qué significa despacito.