Hello Jai, Ben here - your Shopify Guru!
If you need to limit staff members you can make POS only users who cannot log into the admin panel. You would need the retail package for this feature to be activated.
Having different user levels would be a beniefitial feature and you are not the only other merchant that has requested it. Our developers are aware of the feature request. We are working to improve the features of our software all the time. This may very well become integrated in the future but for now there is no way around this but using the POS only accounts with the retail package.
I hope this helps! Feel free to reach out if you have any further questions :)
Ben C - Shopify Guru