You need a hardware wallet. ie. Trezor, Ledger, etc.

Take your machine OFFLINE. Do it on a machine with a fresh boot USB so you avoid keyloggers and other spyware they jam on these computers.

Generate the word list and WRITE IT DOWN. Store that list in several safe places. Fires happen and you don't want your crypto "going up in smoke".

Once your private key is generated, you can go back online, but only plug in the hardware wallet when you are sending from it. You can save the receive addy on a text note pad, because it's a PUBLIC address, it can receive anything.

To send, plug in your hardware wallet and start the wallet, then use the send function.