Noting is secure nowadays. Neither any exchange or any online wallet can secure from theft. However, there is a silver lining. If you know how to configure a hard wallet, you most definitely should. it's the most secure way to store your crypto, though given that your hard disk where you store your hard wallet should not get corrupted. In order to prevent that, you should take multiple backups. Else one way is to evenly distribute your crypto balance across different online wallets. But refrain from exchanges. they are very insecure and most liable to attacks and thefts.