Recommendations for Python web GUI

I am a Python newbie and currently I am writing a script in Python which is analyzing different streams and it is returning some of their audio/video parameters. It is based on ffmpeg and more specifically ffprobe. Since the script is running on a Linux server and it is only CLI based, I would like to create a simple user interface. For example NGINX server and a simple webGUI, where I can define the URL path or upload the file and then see these audio/video parameters in the same page with the option to export the results in different file formats. It should also support file upload functionality and selection of which parameters I want to see.

So I am looking for recommendations about the webGUI. I was looking on the web, and I think Flask could do something similar, but it looks a bit too complicated to me. And I suppose I will need to write the HTML and CSS. So ultimately I am looking for something like Wordpress, where I can define the names of the fields etc. without writing the CSS and HTML part. Is there something like this? If not what are you recommendations?