https://wiki.debian.org/BackupAndRecoveryI can't see anything about backup!!!
Because it is a different topic, so after reading some about it, if you feel you must do so,
start a new topic about making backups, which files to back up , etc.
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If you had looked at and read the link, you would see:
From:https://packages.debian.org/buster/nvidia-detect
All that package is , is a script that checks your system, it then makes a recommendationThe 'nvidia-detect' script in this package checks for an NVIDIA GPU in the system and recommends one of the non-free accelerated driver meta-packages (nvidia-driver, nvidia-legacy-390xx-driver, or nvidia-legacy-340xx-driver) for installation.
about which one of packages should be installed. It does not install anything, and is not at all likely to harm your system.
If you do decide to install one, then yes you should make a good back up of your entire system, especially if it is all ready working OK, In fact it does not make sense to me why you would want to do this, assuming everything is working, but that also is another topic.
My advice is , if you have a working system, learn how to do some more practical things, like making good backups, before trying to experiment with this.