Classify classification of class data in Excel

Hello, I'm posting my first question!

Excelor students - Name of course - Subject classification like this The student is literally a,b,c,d... The major categories are AI, planning, marketing...It's divided into categories.

So what I want to do is I wonder what kind of field each student takes a lot. It's better if you can extract certain keywords, for example, a takes a lot of lectures with "artificial intelligence"

From now on, I'd like to recommend subjects in areas with a lot of interest. How should I write it if I code it with Python?