Read a few articles about immigration. They could be from the place you were browsing, news articles you find through Google, a library reference database such as Britannica Academic, or even a Wikipedia article.
You want to get a bigger picture of the issues around the topic. A quick search in different places shows more specific issues and things related to genetic modification.
|Search Results / Article
|search on immigration filtered to news
|hotels and immigration, immigration reform, southern border, border facilities, spousal immigration
|Britannica Academic (library database)
|search on immigration and United States ⇒ "Immigration" section in "Democracy" article
|some historical background, anti-immigrant sentiment, connection to human rights
|"Immigration to the United States" article
|history of immigration to the U.S.; contemporary immigration; demographic, economic, social, and political effects; legal issues
Based on the background research you've just done, narrow in on a more specific topic. Your project will be much more manageable if you focus on one piece of the larger topic. Here are some examples of narrower takes on the immigration topic: