I have a topic which is, impact of social media on interpersonal communication. and the introduction of the assignment has been done already. The part which a writer has to work on is a background and significance

This is where you explain the context of your proposal and describe in detail why it’s important. Create a separate section to help with the organization and narrative flow of your proposal. Approach writing this section with the thought that you cant assume your readers will know as much about the research problem as you do. Note that this section is not an essay going over everything you have learned about the topic; instead, you must choose what is most relevant in explaining the aims of your research.

To that end, while there are no prescribed rules for establishing the significance of your proposed study, you should attempt to address some or all of the following:

State the research problem and give a more detailed explanation about the purpose of the study than what you stated in the introduction. This is particularly important if the problem is complex or multifaceted.
Present the rationale of your proposed study and clearly indicate why it is worth doing; be sure to answer the “So What? question [i.e., why should anyone care].
Describe the major issues or problems to be addressed by your research. This can be in the form of questions to be addressed. Be sure to note how your proposed study builds on previous assumptions about the research problem.
Explain the methods you plan to use for conducting your research. Clearly identify the key sources you intend to use and explain how they will contribute to your analysis of the topic.
Describe the boundaries of your proposed research in order to provide a clear focus. Where appropriate, state not only what you plan to study, but what aspects of the research problem will be excluded from the study.
If necessary, provide definitions of key concepts or terms.