Your research proposal will be the recipe for your dissertation. Your introduction should clearly state what the proposed research will be about. It is useful to start with a clear formulation of your research question and should include a short version of your literature review.
You will then need to expand on this by explaining:
The literature review should state:
The literature review is an important part of your rationale as it provides a framework for the reader to understand the research question and methodology. It also demonstrates to the reader your awareness of the breadth and diversity of the literature relating to your research question. It is a carefully structured outline of what others have said and done. It also requires critical examination of the related literature including strengths, weaknesses and gaps.
Your supervisor will help you to understand about the breadth of the literature you need to consult.