What kind of flower is this? Why is there a liquid like nectar?

Impatiens Impatiens, Impatiens, belong to Impatiens of Impatiens family, with various species, which are native to Indian, Malaysian and China.

Panicum miliaceum, the plant height is 30-60 cm. The stems are fleshy, reddish brown or light green, often related to color, and the nodes are swollen. The liquid it secretes, like sticky nectar, has medicinal effects.