Your questions are unanswerable, because the situation is permanently fluid.
But more important, your questions are unnecessary, and here’s why:
Undocumented immigration is not, and has never been, a pressing issue for the United States. It is not something you have to worry about. It is not something you have EVER had to worry about. The odds of it affecting your life, or the life of anyone you know, in any kind of negative manner is so minuscule as to be irrelevant. It is much more likely that undocumented immigration affects your life in a positive manner, but even that is a pretty small percentage. The likeliest outcome, by far, is that it affects your life not at all beyond the time that you waste thinking about it.
So the answer to all of the questions you raise is: who cares? Let the experts in that field come up with solutions. Let’s make sure they’re humane solutions in keeping with the principles that have guided this nation from the beginning, as a sanctuary from the rest of the world’s economic and political woes.
Beyond that, stop worrying about it.