Everyone has their own investment approach for Bitcoin investment. Even in the field of security measures are taken from each position as desired. No matter how well you ensure your security measures, you cannot be risk-free.
There is always risk. Risk of loss with your investment, so please only invest money you can afford to lose.
Other risks like storing your bitcoins improperly like on centralized exchanges without full control of your bitcoins because you don't have private keys or mnemonic seeds. Risks like don't have safe and secured wallets to use (non custodial, open source) and backups for wallet recoveries later.
Risk-free does not exist in life. It's only small or big and you only can minimize risk by having good strategy and methods for what you're doing.
Even if a person does not need to know so much before starting to invest, it will necessarily waste his time and he will lag behind in investing. This knowledge may be needed after starting to invest. You can discuss the fundamentals of investing and leave them free to take action.
If you are a long term investor, you only need to understand fundamentals for Bitcoin, choose a good wallet for your Bitcoin storage, make multiple backups, and make sure you hide your investment information with others to avoid risks of hack and physical attacks.
Investors are different than traders, and they don't have to spend or waste too much time in the market like traders.