We can not answer your question because you have not said which country's immigration policies you want to know about. All countries have immigration policies!

how does immigration affects individual

he is going to secure the border.

yes

Segregation that occurs due to laws or administrative decisions can include racially discriminatory housing policies, unequal funding for schools based on the neighborhood's demographics, and voting restrictions that disproportionately impact minority communities. These policies can perpetuate systemic inequalities and limit opportunities for marginalized groups.