Visa advice

To get the best visa, you want to land the best job. And to get the best job (with a good salary, perks, insurance & other advantages) you want to first line up, apply for and then land the job you are looking from folks in your home country, My advice is simple. Secure the job in say Ireland or Italy first and then - and only then - head to Nepal to educate Nepalese children or adults here afterwards - if that is what you want to do.
To save you a lot of red tape, time consuming formalities and expense too, ask the learning institution you are going to be working for, to secure the nepalese visa - for you - on your behalf.  If they already have a school, college or other institution operating here in Nepal, that should not be a problem. Save you a lot of headaches and insure you get good pay too. Another advantage: it"s not uncommon for EU based educators to pay their staff members living and working here in Euros every month. That would be my advice.

thanks very very much

That is a great suggestion posted already about a work visa. You can also get an education visa if you want to study the Nepali language. How long do you want to stay here? Have you been here before? Maybe there is something else if we have more info.

I really admire anyone who wants to learn the nepali language - an Indo-Aryan language rarely spoken outside of its borders. If you don"t speak Hindi, it will not be easy to learn nepali. As everyone knows, Nepali is based on Sanskrit - so their alphabet is totally different from the alphabet we learned in old Europe. The sounds/pronunciation are so vastly different, and as for word order, here is one example:
Nepali:  "Ma patrikaar bhayera dui barsha summa kaam gar-ey"
English translation:   I worked as a journalist for two years  - BUT if you translate literally without changing the word order:         I journalist two years until work did
Learning how to say Namaste, Dhannyabbadd and Swagatom is one thing but I know people who took 45 hours of private lessons with less than sterling results! As for me, I tried to learn it from a nepali friend who came to the house to give me lessons 3 times a week...until I finally gave up!
Good luck to you.

Ye, it's so difficult. Even after 9 years, I  can't even pick the few words I do know out of a sentence. Then when I try to say something no one understands me. I really wish I had a better ability to learn it. However, I must say that I can read it because it's so phenetic. I like reading it.