You use the private key to send funds from an account. It is the secret half of your address and is a string of 64 hexadecimal characters. If you write down your private key differently today than yesterday, you will be accessing a different wallet. Never write your private key by hand.
A private key typically looks like this: afdfd9c3d2095ef696594f6cedcae59e72dcd697e2a7521b1578140422a4f890.
Without your private key, you cannot access your funds. To keep it secure and easier to retrieve and remember, you can save the private key using a keystore (file or string) or mnemonic phrase.
A step-by-step guide to purchasing and selling crypto on OKX,
Step 1: Log in to your OKX account
Before you can start buying or selling cryptocurrency on OKX, you must first log in to your OKX account. If you do not yet have an account, click Sign up and complete the registration process.
Step 2: Select Buy/Sell
Once you have logged in to your OKX account, click Buy Crypto in the upper left-hand corner of the screen to get started.
Step 3: Select your purchasing method
The next step is to choose how you would like to buy or sell . There are two primary options on OKX: Express and P2P trade.
Finally, simply confirm your transaction details.