Why are red people put on national internment zones (reservations) but not black people?

Because Democrats have kept it from happening.

Nobody is "put" on reservations anymore.  They were established over a century ago as compensation for lands from which natives were relocated by treaty or by force. They were not designed as "internment" centers but rather places where Natives could be enticed to remain peaceably in return for some measure of sovereignty.

Asking if they got a "raw deal" is certainly valid, and Natives were clearly subjected to mistreatment, but the characterization of reservations as places of imprisonment is historically inaccurate.

Blacks were not relocated because, quite simply, they had no territorial claims that conflicted with the Federal Government's agenda. The first blacks arrived at the same time as whites, many as slaves but some as settlers too.  In effect, they were part of the same overall system that placed "red people" on reservations.

The land used to belong to the Native Americans. Black people used to be slaves. That distinction explains the reservations, but both minorities suffer from discrimination.

Your birth certificate is an apology letter from the condom factory.