If organisms stop reproducticing, no new living organisms can be produced. So, the entire species will die.
If humans stop reproducing, no babies will be produced. So, after about 100-150 years, humans would be old and all humans would have died, and humans would be extint.
When all the organisms stop reproducing, the entire earth will have only rocks , sand, mud and water, with no living beings in it.
When the living organisms grow old and die, no new organisms can replace them. So, there will be nothing living left on earth after few years.