How does Hansberry make the opening scene of A Raisin in the Sun a significant one?

Lorraine Hansberry opens the play with a description of the Younger's old, cramped apartment, which is much too small for the rather large family. The apartment and the worn-down furniture correspond to the family's current situation. The play begins with Ruth waking up Travis, who sleeps on the couch, before she begins making breakfast for her husband, Walter. When Walter enters the scene, he immediately asks Ruth about the insurance check, and the couple begins to bicker with each other. Ruth and Walter's relationship is clearly strained, and Walter proceeds to give Travis money, despite Ruth's disapproval. After Travis leaves for school, Walter begins talking about his business idea with Willy Harris, and Ruth mentions that his business partner is a "good-for-nothing loudmouth." Walter responds to Ruth's comment with a passionate speech about being tired and stressed out all of the time. Through Walter's speech, Hansberry illustrates his dream of using the insurance check to invest in his liquor business. However, Ruth simply replies to her husband's dreams by telling him to eat his eggs. Walter's plea and Ruth's response creates sympathy for his character.
When Beneatha enters the scene, she is portrayed as a young, educated woman who is as intense as her brother. Walter once again mentions the insurance check, and Beneatha responds by telling him that it belongs to Mama. Walter then criticizes Beneatha for wanting to become a doctor, and she responds by ridiculing his plan to invest in a liquor business. Their interaction illustrates the tension among the family members and further develops the theme of attaining one's dream.
After Walter leaves for work, Lena enters the scene and has a conversation with Ruth. Ruth attempts to influence Lena's decision to let Walter invest in the liquor business in the hopes that he will be happy and their marriage will prosper. However, Lena detests the idea of going into the liquor business and expresses her own dream of buying a home. Hansberry further characterizes Beneatha by portraying her as an ambivalent girl with fleeting interests. Hansberry also depicts the tension between Ruth and Lena's views regarding men, which contrast with Beneatha's modern ideas of romance. When the conversation shifts to the topic of God, Beneatha mentions that she does not believe in God. Lena responds by powerfully slapping Beneatha in the face and making her say, "In my mother's house there is still a God" (Hansberry, 9). Lena's display of authority establishes her as the head of the household, which indicates that she has the final say in how the insurance money will be spent. The scene ends with Lena talking to Ruth about her "strong-willed" children, and Ruth loses consciousness as Lena is watering her plant.
Hansberry depicts the conflicts of interest regarding how to spend Lena's insurance check while simultaneously characterizing each member of the Younger family. While Walter Jr. is the play's protagonist, Lena is depicted as the authority figure in the home. The tension between each character is illustrated, and the audience wonders whose dream will come to fruition. Both Walter and Beneatha are portrayed as strong-willed individuals, and nobody in the family seems content with their current situation. The decision regarding how to spend the insurance money drives the plot, as each character wishes to improve their life.