It is often useful to differentiate between "concentration camps" and "death camps" or "extermination camps". The Nazis had both. Some of their concentration camps were focused on concentrating and detaining people, some of them also systematically killed them -- they are not the same. If you fail to make this distinction, then saying "America has concentration camps" could make it sound like they're running extermination camps.
The US does to my knowledge not yet have those, nor as large-scale application of concentration camps as Germany did, and whether you even want to use the term "concentration camp" rather than something more like "detention facility" is up to you, but the federal government certainly has camps where people detained by ICE are being concentrated. Sometimes they are also subject to human rights abuses and/or die there.
Here's one of these camps, for example: https://en.wikipedia.org/wiki/Camp_East_Montana
Here is a list of people dying under ICE detention: https://en.wikipedia.org/wiki/List_of_deaths_in_ICE_detentio...