You already have this functionality: If you click on the tag, every topic labeled with the tag will be shown.
A topic can be assigned only to one category. If you still want to have the special “video” category, you can either a) move your topics there or b) create new posts with references to the original posts.
Do you want the topics to be moved to the new category, or available in the new category somewhat like a crosspost? The latter is not possible in Discourse.
As far as I know, there’s no setting to automatically move a topic from one category to another based on its tags.
If you want t move XX existing topics manually, you can select them after filtering them by tag, then bulk move them through the interface.
You can also use a webhook to move a topic in a certain category when it is posed based on its tags, but I’d say it’s better not to allow certain tags to be used outside this category.
At the least – you know when you click a tag it takes you to the page with all the other same tags? I need for someone to be able to click a category , and take me to that list of tags. It’s for presentation, readability, navigation purposes.
I know I can limit tags to certain categories but that’s not what I’m after
Is that possible? Just for a single category
Meaning I click a Category, and a takes me to the tags page with tags “Videos” , but when I click Category, and only for that category