for example if i only use it to browse the internet and maybe download games from play store but i dont install extensions and use https only, can i still be hacked and my operating system destroyed?? what can i do to avoid that?? i only use my chromebook for python
You don’t necessarily need to do something for the device to be hacked. There could be an exploit that affects all devices running ChromeOS (or any OS for that matter).
TL;DR: Yes you can.