I'm afraid that your misunderstandings are so total that it will take a very long time for you to get the underpinnings you need here.
There are many books that are more carefully written than any posts here are going to be. They might help you get enough understanding to be able to ask better questions and understand what you are being told.
Now, about the galloping goalposts.
We started this thread with:
.too bad mutations are never beneficial to any species whatsoever.
Now that this has been shown to be an utterly incorrect statement you wish to discuss speciation without the courtesy to admit that you were wrong.
When you have gotten that clear this thread will be finished and another thread on speciation can be started.
Speciation is off topic here and not what you were originally talking about.