The last chapter of a dissertation is chapter 5. It is written to give meaning to the results. By tying the results with the past theories, predicted outcomes, research, and policy.
It should be divided into three main parts.
Conclusion: It covers the concluding research purpose-driven through research aim, answer to research question and comparison of predictive and actual results.
Interpretation: What, why and how should it happen? It covers all the explanatory part for the end of your dissertation.
Recommendation: Finally, there should be a recommendation for future research. Based on the limitation of the area, population, sample size etc.