Show Categories and tags

Hi
I am using Alloy.
Could you provide a way to “see” and work on the permited Tags and Categories.
For example a dropdown list, where one can see the already used/created Categories would be great.
Or… it might be already backed into the product. But I do not know how to see/find the Categories i already used. Is there a way?
Thank you.

@Pierre Hi, you can use the category list stack provided with Alloy, there’s not for tags. Cheers.