I don’t know what you mean by “activate a tag”. If you want to select a certain document (tab), then you can do using Documents colleciton and Document.Activate method.
When you do a “Find in Files” or, use the FindAll.vbee macro, the output in the new tab is formatted with a tag (a link to the file and the line of that file) with a display of the line it found the search parameter on.
I am wondering if its possible to activate (click) this tag in a macro to jump to that line in the original file.
Yes, you can use the Tag Jump command.