Print out your syllabus. Go through 3 past papers. Mark which questions belong to which unit. You will quickly see that Unit 2 and Unit 4 carry 60% of the marks.

After conducting research, I found that there are a few websites that provide access to Annai Poopathi past papers. Here are a few links:

⚠️ Beware of fake websites offering “Annai Poopathi past papers” for ₹500 or more. Legitimate university papers are always free.

Do you need me to make any changes or add anything?

https://www.oldquestionpapers.net/madras-university/question-papers/annai-poopathi/ (Contains 2015–2022 papers in ZIP/PDF)