Books. Don't bother with anything else that tries to teach you 70 years of complex history in a few minutes.
I recommend Israel: A Concise History of a Nation Reborn by Daniel Gordis. It's not too long, and it offers an overview of Israel's history - from the beginning of the Zionist movement in the 19th century to present day.
A standard relatively objective history like Daniel Gordis’ “Israel: A Concise History of a Nation Reborn” will discuss borders and such (with a lot more context to help you understand).