Clarifying the Elusive Concept of 'Basic Structure'

Hey guys, I'm having trouble grasping the concept of 'Basic Structure' as per Article 368(2) of the Constitution. Textbooks just explain it in vague terms, and I'm finding it hard to relate it to real-life scenarios. Can someone please provide a clear example or definition of what constitutes the 'Basic Structure' of the Indian Constitution? Is it purely about the 'Preamble' or does it extend to other fundamental rights like 'Equality before Law' or 'Right to Freedom'? Something concrete, not just abstract theories, would be super helpful for CUET PG Law preparation!