What are the common guidelines for writing a thesis in European and English-speaking countries?
There are some common structures that show up frequently (e.g. Introduction-Background-Methods-Results-Discussion is common for experiment-based papers), but they are different for different fields, and it is not mandatory to follow them. Some universities (mine among them, but I'm not in Europe) give "Thesis Writing" classes, where you get an overview of the various strategies. You could look up materials from these classes, maybe they will help.