opensource web application for easy creation of sheets with automatic categories and search

I'd like to build a website with easy management. In admin mode i would like to add sheets of articles with some specific tags that will be tagged as categories.

In user-mode view-mode will show the search tool for generic terms but one automatic menu must be showed with accesses for all stored sheets of each category.

In admin-mode users can easily add new sheets with category tags and contents (pages with images/videos and description.

Is there any open-source web application that can give me these bundles of functionalities?

the website must appears to be one shop-themed web app. but without the cart and e-commerce functions.

Thanks in advance