Where is a good place to start investing and what would you all recommend?

I am 20M and have saved up a small chunk of change from working and would like to start investing for my future. I have 25k sitting and was wondering if a IRA is good idea or to look into the S&P 500. If anyone recommends either, where should I go to get started? My bank offers an investment account that they manage and I would be planning on putting all 25k into it if I do go that route. I am open to all suggestions and would be appreciative in getting advice, thank you.