Ok, and then how do you get the money out of your wallet? Just click on the "send" option and enter my exchange address and then withdraw?
You asked how to buy and store Bitcoin, so I assume that you want to receive coins to your wallet, and not send them out of your wallet, right?
If you bought bitcoins in a centralized exchange (Coinbase, Binance, OKX,...) then you should have the option to withdraw coins from the exchange to your personal wallet. However, the withdrawal process may vary slightly depending on the specific exchange. I recommend checking the instructions directly on your chosen exchange's website for detailed guidance.