Keeping our bitcoin safe is not easy because there's have many hackers that have a chance to hack our bitcoin. Putting codes in our wallet can help us because it is easy for now to hack Bitcoin without codes. Be careful who you trust because sometimes they tempted to have money.
No, it is easy to safe our bitcoin, as long as you can keep in your wallet without any chance to use for buying, selling, or making a transaction then you don't have to worry. The codes will make our account more secure, so they don't have a chance to hack our wallet, but this is not a 100% guarantee. Besides that, you need to keep your private keys in a safe place and only you that will know that places.