Each travel insurance provider has their list of pre-requisites that must be completed in order to buy a travel insurance policy. You will be asked these when you try to buy online or visit one of their customer service center. In most cases, the travel insurance company is looking for two types of information i.e. personal and travel details.
In personal information, you will be required to provide necessary documents like NIC or DOB certificates for identification purposes. Some companies may also require information from your travel documents.
For travel details, the company will ask you to reveal as much information as possible. Most probably you will be asked to confirm the information about your destination, any travel companies involved, hotels, flights, total cost and how the cost is divided per person (if it is a family package).
You must understand that travel insurance is providing you cover for so many things and they will request you for all the relevant information. However, it will be for official use only and your privacy and confidentiality will be respected.