Here is an helpful template you can use (of course with personally relevant modifications).
Hon. Min. of External Affairs
Subject: Please take cognizance of abuse of Indian students in USA and issue a travel advisory against Indian students pursuing education in USA.
I am ___, I studied in USA in ___ University. Given my experience in USA, I would like to bring to your attention the gross violation of basic human rights that Indian students have to suffer in USA. I regret my decision I would have acted differently, had I have been better informed.
I have seen you talk on various international forums with courage and articulation that befits your post and you have been unapologetic defender of India’s national interests.
US consulates in India, routinely trap Indian students into studying in USA. However they misrepresent facts and often confusion students trapping them into US university system and uses them as labor force without giving them basic rights accorded to other nationalities.
India being a free and liberal democracy, the government can not make individuals make specific choices but it is well within governments power and duty to ensure that its citizens have all the information they have to make good decisions. I would request you to ensure that the following information be presented to all Indian citizens willing to study abroad. This is also in the best interest of Indian government as most of these students borrow from government owned PSU banks for their education and Indian government loses both talent and foreign currency.
Ensure that Indian students know about country of birth discrimination in US laws.
It is important that all Indians who move to USA for study or work should know that US law treats Indian born people differently from others. While a Pakistani or Nepali might be able to green card in USA within 2 years, an Indian is asked to wait for 150 years. This means no Indian can get permanent residentship or citizenship in USA in a reasonable time anymore.
US Consulates in India routinely mistreat Indians and often separate families.
US consulates in India are notoriously slow for India. US has only 4 consulates in India which is significantly less that what USA has in Spain, France or even Canadian provinces like Quebec. Note that USA-India trade relationships are one of the largest in the world and US tech industry relies heavily on India-US people movement. 
Despite all this typical wait time today to get a B1 visa in USA is two years. This means if a student goes to USA for education and his/her parents want to visit their child in USA, they can not do so. They wont even be able to attend the graduation ceremony.
It is believed that this delay is a deliberate tactic to racially target Indian immigrants.
Family separation of long time Indian immigrants in USA.
Due to country of birth discrimination, Indian immigrants never get citizenship in USA and hence they have to keep renewing their visas. US consulates often refused to renew the visas in reasonable time due to which people are forced to either quit their jobs or separated from families or are unable to attend funerals and dying relatives in India.
Labor abuse and discrimination.
Because Indians can not get green card in USA anymore, such people are likely to be subjected to abuse at the hands of their employers in USA. They will be refused promotions, better salaries and constantly harassed. They are also forced to pay additional taxes like social security something which they will never benefit from.
Racial targeting by different political outfits.
In past several Indians have been fatally shot because of their nationality in USA. Several radical political groups in USA spread hatred towards Indian workers precisely because of their success. Some of these organizations are funded and supported by eugenics supporting groups, Pakistani ISI funded groups and other groups which wish harm upon India and its expats.
Why Ministry of External Affairs is morally obligated to take action.
India as a rising power must come to the defense of its citizens no matter where they are and even if these citizens are willing to immigrate to other nations. Indian expats not only send India huge remittances but they also play a big role in funding new businesses, brining new know how and helping India secure its place in the world. This pipeline of human talent must not be allowed to be abused by racism and discrimination.
Respectfully, I ___ would request you to consider this request and at least make a public acknowledgement of this problem.
 https://www.cato.org/blog/150-year-wait-indian-immigrants-advanced-degrees  https://marginalrevolution.com/marginalrevolution/2022/12/why-the-united-states-should-open-new-consulates-in-india.html