Question

what is meant by living beings

Answer 1

The criteria can at times be ambiguous and may or may not define viruses, viroids, or potential artificial life as "living". ... The current definition is that organisms maintain homeostasis, are composed of cells, undergo metabolism, can grow, adapt to their environment, respond to stimuli, and reproduce.

Answer 2

Any organism capable of
Growth, 
Reproduction, 
Metabolism and 
possessing Consciousness 
is said to be a Living Being.

In most lower organisms like Bacteria and other unicellular beings Growth is synonymous with Reproduction, I.e., they grow by dividing. No genetic variation. Each is a clone of other. Potentially immortal.