1. What is an embassy of a country(India)?
In simple terms an embassy is a place in a country with officials of another country. For instance, the India embassy in England will have Indian official geographically present in a designated place (India House, Aldwych, London WC2B 4NA, United Kingdom) in England.
2. How is the head of an embassy of a country(India)?
The top most official is often referred to as Ambassador or High Commissioner. For instance, the Indian High commissioner to England is Mrs Ruchi Ghanashyam. Usually, the officials are diplomats or with an Indian foreign service background.
3. What is the role and function of an embassy (India)?
The main role is protect the core values of interest of the country and the people that it represents. For instance the Indian embassy in England will help Indian citizens to get consular services, guidance of rights and legal advice. For instance, there was a recent burning of our National flag in Jan 2019 at London. The Indian mission (embassy) complained and lodged a protest.
4. Who, when and for what can a person or a nationality approach their embassy(India)?
Any Indian citizen, holder of Indian passport, Holder of OCI or PIO cards (overseas citizens of India, People of Indian origin), new born children of Indian parents can approach them anytime with prior appointment. In case of dire emergencies when life is at threat, an Indian citizen can seek emergency assistance at anytime.
5. What is the privileges of an embassy and the person working in it.(India)?
The basic privilege is that of a certain degree of immunity or exception from the local laws governing the country in which the Embassy is located. For example, to the common man, the Indian embassy in England, is the extension of India was far as basic rights are concerned. The UK authorities cannot enter the embassy without follow the existing protocols. Any attack ( verbal or physical) on an embassy amounts to attack on the country that the embassy represents. Such events are taken seriously. For certain officials and packages full diplomatic immunity can be provided under specific circumstances. This is often misused in the past during the Cold war and by certain countries.
6. What to do, if we don't get help from our embassy(India)?
If a person is unable to get help, he or she needs to contact the ministry of external affairs. Most embassies have a system of complaints and grievance readdressal. For instance, if you not happy about the help from Indian embassy in London, you can complain at firstname.lastname@example.org.
7. What all service do an embassy provide for its people or nationality.(India)?
Most of the services provided are visa services, help in extending passports, applying for new passports, grant of emergency travel documents, assistance/guidance in case of detention or arrest. It also offers services to journalists, film/TV crews etc. From time to time, it issues guidance and travel alerts to Indian citizens and Indian origin people regarding travel to that particular country in which the embassy in located. For instance, this is the travel guidance given by the Indian embassy in London (https://www.hcilondon.gov.in/pages?id=eyJpdiI6Im1FXC9NS1FXYUp1Z1gyZGNWak82RW5BPT0iLCJ2YWx1ZSI6IkpiazhsaXl4VERGZEtzWThQZnNjbGc9PSIsIm1hYyI6ImYwZDYwNTc3MTIyNzg4NTJhNTUxNjU2YzRmMWNiZDRmNGI1YTZhYjE0NzQ5OWJhYTBlNmY4ZGY4NDE3ZDQ5ZGIifQ==&subid=eyJpdiI6IkJwdEwycVdoZzVvKzJ5bVwvR0R0clV3PT0iLCJ2YWx1ZSI6Imk4c1RabURjbkpTYXBSZkNTSlBpTWc9PSIsIm1hYyI6IjJlZDA4YmFlYzBmNTI5YTliZjlhOTU3YzFlYWI0OGI4YjM4ZDRmMzRjYjYzNzM1Yzg0M2QxOWE2ZjRkYzQ3NmUifQ==)
8. Do all country have their embassy throughout the world?
Most countries have but there are exceptions. For instance, USA does not have embassy in Bhutan, North Korea, Iran. Some countries are so small and or so poor that they cannot afford to have embassies all around the world. Some countries, instead of a full embassy, have a simple office that accepts documents for it's citizens.
This is a brief information about the Indian embassy, the staff, pay etc in Israel (https://www.indembassyisrael.gov.in/pdf/RTI_info_and_Annexure_II_III.pdf).
You can also refer these books.
The Modern Diplomatic Mission by David M. Malone
The Oxford Handbook of Modern Diplomacy
Edited by Andrew F. Cooper, Jorge Heine, and Ramesh Thakur