I studied Beowulf as part of my degree and the whole point of studying something like that is that someone who knows a lot more than you, having spent their life at it, will explain stuff like that. So for instance, having been taught about it I can tell you that a ‘foundling’ is an abandoned child who has been found and adopted, and the ‘whale road’ is a poetic way of talking about the sea because it is the place where whales move about like people move on roads. It’s a bit like learning to do cryptic crosswords clues. After a while, you start to get your eye in for that kind of poetry and can make good guesses even without being told. Some old poetry (like Norse Skaldic poetry) was hard to understand even for the people it was written for. It was supposed to be like the riddles in Lord of the Rings. There’s a great story about an Icelander who killed an enemy - if you did that you had to publicly own up to it to avoid being outlawed for ‘secret murder’ which was dishonourable. But if you did own up to it, the dead man’s relatives would quite legally come after you to kill you in revenge. So this guy who was a skilled poet announced his killing in the marketplace only he did it in such skilful and complex poetry that nobody could work out what he was saying until he was well away!