Think of virus like a bag–a bag filled with genetic material. Pretend that the bag, a circular bag, is the envelop of a virus. Inside the bag, or the virus’s envelop, you can find either DNA or RNA (i.e. the genetic information of the virus).
SARS-CoV-2 is the kind of bag that contains RNA, not DNA. In fact, the SARS-CoV-2 bag only contains a long strand of RNA. The “bag” or the envelop of SARS-CoV-2, like many other viruses, is made of lipid bilayers, i.e. fatty acids chains organized in two layers. (See Figure 1 below)