The goal of Research Methodology is to learn how research is being done, and to put that knowledge into practice. You learn how to apply a great number of statistical techniques, draw conclusions from those, and determine what statistical technique would be suitable for a given dataset and/or research question. In contrast to your Statistics course, here the emphasis lies on interpreting results and communicating those to the world at large. In other words, you learn how to take a step back and think about what you can conclude from a certain experiment or statistical test.
Biostatistics (also known as biometry) are the development and application of statistical methods to a wide range of topics in biology. It encompasses the design of biological experiments, the collection and analysis of data from those experiments and the interpretation of the results.
Research methodology simply refers to the practical “how” of any given piece of research. More specifically, it’s about how a researcher systematically designs a study to ensure valid and reliable results that address the research aims and objectives.