Not sure of the nature of your qualification, but dissertation suggests an honours degree. Unless your institute states otherwise, a level 6 dissertation is normally12 to 15 thousand words, (not inclusive of appendices), and constitutes more than just a literature review. The structure is; title, abstract, contents list (chapters, list of figures and glossary), introduction, literature review, methodology, nature of experiments, discussion, conclusions and bibliography. Much of the emphasis should be on methodology as this determines the validity of yous study. Take this element of your research seriously as this document might define your academic progress going forward. This is certainly true of masters and doctoral output. Sorry if this sounds tough, but as a doctor and university lecturer I have set, supervised and graded many dissertations and this is the reality.
Happy to help further if needed.