Clarification how staging site works
I am new to craftcms and webdev. Therefore I am unable to tell you an exact route, but this can definitely be solved, I already read about it. This guy has excellent tutorials about craftcms and development and these two topics could solve your question. Just give it a spin and read through:

https://nystudio107.com/blog/database-asset-syncing-between-environments-in-craft-cms

https://nystudio107.com/blog/multi-environment-config-for-craft-cms