As a private key owner, you must be careful of fake sites that want your private key, this case has often happened to some people
In fact under no circumstance should you disclose your private keys to any site or individual. When trading on centralized exchanges, your private keys are not required, you simply deposit and withdraw to your wallet.
Decentralized exchanges demands for your private keys, but you can always log in with metamask to be absolutely secure.
And also beware of pop-up ads requesting for private details.