If you die then your BTC will be secure in your wallet. But if you tell your private keys and password to anyone then he will access you wallet otherwise your BTC will Secured in your wallet for life time.
This is what makes us always have to open any information to trusted people such as family members, I wrote in the book several private keys such as bitcoin, ethereum, Terra and others, by writing the private key then if we die there will be a family who can use our cryptocurrencies so that they can use.