A teaching is Buddhism if it covers three concepts, anicca, anatta and nibbana. All commonly accepted schools in Buddhism all have these 3 concepts as the core. They differ only in the matters of specific Practices, focuses and implications of these concepts. If you do your best to understand and experience these 3 concepts, that's really all you need to be on the right Path. The benefit of being a bhikkhus might be that it gives you more time to think about these 3 concepts. Maybe.