Genealogy in the bible can be difficult at times. I'm not a big fan of spending a lot of time looking at it. But it has a key importance.
The bible is a series of events that took place in specific times and places. The events in the book are actually about things that took place.
The stories in the bible are not of the sort of Greek Mythology. The stories in the bible took place in a specific time and place.
Abraham, Moses, Jesus, ect were real people. A key to evangelism, defending Christianity, or simply understanding Christianity is to realize that these are real events that took place.
Of course few non Christian will see these historical events as having any significance. So understanding the historicity of Christianity is not enough, but it is a key starting point.
What is important is understanding the true nature behind what the bible reveals of the historicity. This is a sort of history which one can place ones eternal trust in.