Ali
@portofacil is right server do require your attention, its not like shared hosting where your host manage server for you.
but if you are not experienced and short on budget you can do following, it requires minimal skill.
take daily backup of your website ( dont keep it on same server send it to the remote storage server like gdrive or s3 )
periodically (at least weekly) run this command via ssh
wo maintenance
wo stack upgrade --all
wo clean --all
and you are good to go , in worst case you already have daily backup set so you can always spinup new vm and restore the backup.
but with this method don't expect high reliability or availability of your website, things can go south anytime
if you are running a profitable website/business its always best to hire professional.