Is it normal i think holding illegal immigrants in holding camps is ethical
This is referring to the U.S.-Mexico border. I look at it this way. They are basically in a jail they walked in by crossing into a country illegally without application of entry or citizenship. Every country has the right to choose who can and cannot enter. Even though it may seem unethical, It is a nation's right. Some nations murder people who cross illegally regardless of reason.
Illegal immigration is really the equivalent of trespassing into an area that does not want someone.
If someone came onto your property and refused to leave, you would probably alert authorities and have them removed. It is no different on a national basis.
If someone immigrated through the citizenship process legally and it is granted by that government, then they will be welcomed in without much objection.