thank you for your inputs so far. My lecture covered little bit on Laws of Manu.

Manusmriti also known as Manava-Dharmasastra is the earliest metrical work of the Dharmasastra textual tradition of Hinduism. It is better known as Laws of Manu in English.
Dharmasastra or Laws of Manu is basically a source of religious law describing the life of an ideal householder and, second, as symbol of the summation of Hindu knowledge about religion, law, ethics, etc.

Obama i think you are in the right direction  when you said Kirantis are in fact Hindus.

Professor Sudarshan Raj Tiwari said that the Kirats came from the Indus-Saraswati Valley.
The Manusmriti identifies the Kiratas as one of the eleven tribes who inhabited the Indus-Saraswoti region. (The Brick and the Bull, 2002)

In Manu's Dharmashastra (X.44) Kiratas are mentioned as degraded Kshatriyas ,which meant that they were considered to be of advanced group of miliraty might but because the Kiratas did not conform with rules and norms of the Manava-Dharmasastra(Laws of Manu), they were degraded into lower position.

Now one of my assignment was to list some examples of Manava-Dharmasastra(Laws of Manu) and analysis these rules and norms that had to be carried out in order to retain the high-caste position. Failing to do so meant degraded into lower status as the Kiratas.
Now my question is what are these rules and norms that have to be carried out in order to retain the high status?
Is sati one of the form of ritual listed in laws of manu?
What are some things we observed according to Manava-Dharmasastra when living abroad that can
result us being degraded into lower status?

Thank you.