Werner,
Thanks for reaching out! Unfortunately, the Community add-on currently only supports Categories on the event submission form. It would take a pretty significant modification to the plugin in order to include Tags that users can submit.
If this is something you’d like to see in a future release, I would suggest submitting it as an idea on our UserVoice page. Our team periodically reviews the most popular ideas for possible inclusion in a future release of the plugin.
Hopefully that helps to answer your questions, but please let me know if I can help further. Thanks! ๐
-Casey-