I think keys are very important thangs for every crypto workers or traders so that it should be stored into safe and secure places. Currently i am using a hardware wallet and offline PC where no internet can connected so that any malware can affect it. thanks.
But whenever you need to make a transaction even through the hardware wallet you will need an active internet connection to connect with the wallet app and pop up the transaction on blockchain for other nodes to verify and include in block.So the safety is don't click on malicious links or download fake apps while keeping full security of your funds.