This, in fact, is a very complex question. Some countries do not require visitors to apply for a visa in advance for short visits. Certain regulations do allow travellers to visit the USA on the Visa Waiver Program or a Visitor Visa for the purpose of making an investment, if otherwise eligible. B1 visa is used by the travelers for the purpose of business and B2 visa is used by the travelers for the purpose of tourism or pleasure.
Once in the country, the validity period of a visa or authorized stay can often be extended for a fee at the discretion of immigration authorities. The visa validity then indicates the time period when entry is permitted into the country. The documents necessary for applying for the eTA are a valid passport and email address and a debit or credit card.
The purpose of your stay must be for 90 days or less, and reason for your visit must be for tourism or business. Even though the traveler is going to conduct just one business meeting while in America, they are required to report it and enter as a business visitor.
The place to get a visa is the embassy or consulate of the country you plan to visit. Either way, you will have to appear at a visa application center in your country. Retirement visas are meant for self-funded retirees who are 55 years or older, have no dependents (other than a spouse who can be any age), and who want to reside in Australia during their retirement years.
These agencies are authorized by the foreign authority, embassy, or consulate to represent international travellers who are unable or unwilling to travel to the embassy and apply in person. The approved e-Visa allows the visitors to remain in Turkey for a period up to 90 days.