I currently have some BTCs in coinbase that I bought with my own money. Is it not secure? I still don't quite understand the concept of putting it in a "wallet" that resides in your harddrive.... I feel like that is more risky. What if the file accidentally gets deleted or my computer crashes?
You really need to learn the difference between paper wallets, cold software wallets, hot software wallets and online (web) wallets.
Try each in turn and perform some transactions from each with small amounts of bitcoin. Learn how to best secure and backup each of them.
Buying $1mn of bitcoins without knowing each of these important concepts in detail seems like a recipe for disaster.