I agree with a lot said, especially about finding what you like. That may change over time, but that's the fun. While I appreciate JRock23's advice, I would add a few thoughts. Make sure you are comfortable accessing a coin's condition within a particular series before buying the key dates. It took me time (and purchases and mistakes) to understand what to look for. I have complete sets of
Buffalo nickels and
Barber halves (except 1). I never bought keys until the end. I am glad because some of the first coins I bought were clunkers, looking back. Part of that was just being new to collecting, but some, like quality of strike, were not. Anyway have fun!