There are many international airlines operating their flight to Kathmandu- the capital city of Nepal. Some of the country has direct flight to Nepal and some has connecting flight via Doha, Abhu Dabi, Istanbul, New Delhi, Shanghai, Beijing, Dhaka, Bangkok, Singapore, Qualampur etc. Visit your nearest travel agency or go through online to get the international flight ticket. It is also possible to get to Nepal by drive through India and China (Zhangbu border). Sunauli, Kakadvitta, Birgunj, Bhairihawa,Mahendra Nagar and Dhangadi are the major entry point of Nepal, if you are coming from India and Kodari is the one and only entry point if you are coming by drive through China.
You can get the visa to Nepal upon your arrival from the Immigration office or from the embassy of Nepal if it exists in your country. However the tourists who are holding the passport of Nigeria, Ghana, Zimbabwe, Switzerland, Cameroon, Somalia, Liberia, Ethiopia, Iraq, Afghanistan and Palestine are not eligible on arrival. A passport size photograph and visa fees of USD 25 for two weeks, USD 40 for one month and USD 100 for three months are applied depending on the length of your stay. Visa can be extended up to 150 days in a year.