As a whole, they’re called Wax Plant, Wax Vine or Honey Plant but these evergreen climbers will have experienced gardeners and newbies smiling from ear to ear when the first flower appears.
Hoyas need as much bright light as possible to bloom indoors. Keep them away from hot, sunny windows & direct afternoon sun. In the darker winter months, you might have to place them in a location with more light.
Variegation varies plant to plant.