In Samuel Selvon's The Lonely Londoners, white people often respond to the immigrants with either a fascination or a hesitancy that borders on revulsion (and sometimes crosses that border). Let's look at this in more detail to get you started on these questions.
Begin by thinking about the reactions of white women to some of the novel's primarily immigrant characters. Men like Bart and Cap may seem exotic and exciting to these women. While Bart falls in love with Beatrice and wants to marry her, however, Cap uses the women's interest to his own advantage, stealing from them and imposing upon their generosity. Bart has no luck marrying Beatrice, though, for her father puts a quick end to the notion, and Beatrice actually disappears.
Other white people respond differently to the immigrants. Some are extremely racist, and it is often due to racism that the immigrants find themselves in low-paying jobs. You might dedicate part of your discussion to the bosses' reactions to the immigrants and their perceptions of immigration.
Still other white people are fearful. Think of the reaction the mother and child on the street have to Galahad. The child is first interested and then fearful. The mother tries to correct the child but is also skittish around Galahad. The child shies away and cries when Galahad pats the little one on the cheek. Galahad is foreign, and they do not know how to respond to him.