Cryptocurrencies can be kept online or offline. If the cryptos are kept on the exchange platforms or other online platforms, it can be lost due to hacks.
So it is important to choose the best wallets that are safe and secure. Please help me in choosing the safest cryptocurrency wallets
It's not wise to store your crypto on exchange wallet because something can go wrong and the exchange may exit. It's wise to choose a wallet based on your budget. I personally use mobile wallet and trust wallet and Imtoken wallet has been my choice. I haven't experienced any issue of hack or loss of digital assets since I started using these wallet and I can say that they are safe.