To secure your wallet, maintain your wallet address details and private key confidential. All transactions will be done in the internet, so careful with your money and wallet. For simple transactions, wallets are very useful and risk-free.
Private key and wallet seed must hold as confidential thing. Apart from that wallet.dat file also to secure it safely. Mostly don't prefer onlinr wallets for your usage. You need to have a desktop wallet or paper wallet to have numurous features.