Hello Yash,
You asked: “Also could you please elaborate ‘contemplate the asubha nature of “mind-pleasing things‘ in this world..”
Asubha means “not fruitful” or “not beneficial.”
That goes with the other three characteristics of nature: anicca, dukkha, and anatta.
First, can you tell me what you understand by anicca, dukkha, and anatta?