Use timeshift, install it, just chose where you want the backups to be installed, preferably a second HD or SD Flash. Chose when like once a day, week at start up for instance and forget it. Then if you screw up your Linux, just start in console mode, timeshift --restore and five mins later your up and running.
If you want just your data to be copied, then Cron
Both are standard Linux programs, often already installed depending on what Linux you have