[nickserv]

Flask (or fastAPI more recently) will give you a basic webserver... and that's about it. You'll have to do everything yourself basically. I would not go this route, unless you have no deadlines and want to learn a lot on the way.

WP will be easy to set up, but adding custom functionality can be a real pain, and lots of plugins are of ... questionable quality, especially regarding security. I personally strongly dislike WP, but it does the job so long as you keep things simple and lock down your plugins.

Django will give you a good structure and some core functionality like login out of the box, and the built-in admin site is great, but you'll need to code your functionality. It looks like you're doing some custom code so this approach could work. You could also use something like django-cms or wagtail if want some of the WP functionality.

https://www.django-cms.org/en/

https://wagtail.org/