Store your coins on non custodial wallets, store your coins on wallets that gives you complete control of your private keys and they don't keep backup. Non custodial wallets are the perfect for storing your Bitcoin. You don't have to be scared of hacks when you use one.
Exactly the problem of online hacks that happen through phishing or it’s like are eliminated when using cold wallets like the hardware wallet or the usb storage method. But other non custodian wallets like the hot wallets are also prone to been hacked if the user doesn’t keeps his keys off the internet. Also the hardware wallets can be compromised if the device is stolen with the pin known to the thief then they could easily access the seed phrase and the keys.
So the warning to OP is do not trust any exchanges most centralized exchange for storing your funds. Use non custodian wallets that are open sourced and also be careful how and where you store your hardware devices, seeds, keys and pins.