Everybody in America is descended from immigrants, besides for the native Americans. In fact, most white people in the US are descended from undocumented aliens from Britain, who didn't have any identification or papers when they arrived. It is hypocritical to be descended from undocumented aliens yourself, but oppose immmigration.
Your logic is astoundingly poor here. A few things....
1. In the way you're using "immigrant", it's possible that even the native americans were technically immigrants. There's an ongoing theory that Native Americans themselves were not originall from north america, but came over on a land bridge connected to Asia.
2. If you use the correct term for immigrant, again early american colonists were not "immigrants". They did not travel to the "new world" in an effort to become a citizen of a foreign state. There was, by and large, no attempts to become part of the native americans civilization. The earliest settlers of America would be more accurately described as something akin to a squatter or an occupier than an immigrant, or in other instances as invaders. They were not "undocumented" because there was generally no desire for or attempt to function within some foreign entity. They were here to take the land for themselves and for their own country, not become part of another.
The comparison between early american settlers and illegal aliens today is a poor and inaccurate one. The latter, by and large, is coming into the country attempting to utilizing the systems and structures related to that country (it's roads, it's services, etc). They are attempting to function within the society of that country (such as by gaining jobs within it) as opposed to simply taking land and establishing their own. They, and many of their advocates, are actively pushing for their acceptance as actual citizens of this country.
Early american settlers were by and large doing none of this. They did not come to Jamestown, for instance, in an effort to become part of the Powhatan. They came to claim it as part of the British Empire. They did not come to Jamestown seeking to live amongst the indians and function within their tribe, they came to establish their own colony modeled in part after british life. They did not expect nor seek the ability go go freely within Powhatan gathering locations, to use their camp fires or their tents as they chose, but rather created their own homes and facilities. They were at best occupiers and at worst invaders.
This is the humor in people continually and repeatedly attempting to push the unthinking and emotionally devoid meme of "undocumented immigrants" as it comes to the early american settlers. It is no more accurate to call the settlers "undocumented immigrants" thanit would be to call the majority of illegal aliens in this country "invaders".