Tagitize is available at https://tagitize.app/download/. Simply enter your email and click the Submit button. The website will then redirect you to an Installers page that looks like this:
Here, download the installer for the Revit versions you want to run Tagitize on. Each installer only installs Tagitize for one Revit version. For example, Tagitize2024.msi will only work with Revit 2024.
You can of course download multiple installers if you need Tagitize on different Revit versions. Each installer works independently so there will be no conflicts.
Likewise, you can uninstall each Tagitize version without affecting the others. To uninstall the plugin, go to your Control Panel > Programs and select the Tagitize version to remove.