Trump has spoken to that. He is going to reassign from other agencies to focus on massive deportation.
I haven't heard any serious plan from anyone, including Trump, about identifying the illegals here and deporting them. This talk about ending sanctuary cities and building a wall is fine but does nothing about the 20 million already here.
I've asked myself, if we had a government serious about removing illegals, precisely how would they go about finding/identifying them?