Simple process. They will ask you to fill your entire biodata with photograph. Then normal questions. Basics of what you know. What task they have. If they give offer letter, they don't provide any compensation part in it it's all verbal promise. (never heard of anybody doing this .. is it even an offer letter with no offer in it?), so that you don't use the offer for getting higher salary from anybody else? (REALLY?? why would a candidate/employee trust you about your promise) All the best to find any professionals joining like this in such non-professional way.