essentially quota offers a (hard) limitation on usable disk space per user. so it is exactly what the name implies - a quota 
@ockythegooner please be more informative:
- what debian are you using
- how did you install (providers template, iso, …)
- is this by any chance a container (ovz/lxc) because if so it’s relying on the hostnodes kernel and specific settings, which means most likely not supported for your VM then
- what filesystem are you using anyway?
keep in mind:
- the package mentioned by @eris does not exists in debian, only ubuntu.
- normally quota should work just fine on debian, however you should enable it already during hestia install
- you might need to adjust your /etc/fstab to enable it per mount point.