I have been studying Judaism alone for the past two years and I really want to convert to Orthodox Judaism. How can I find a rav to mentor me and a Beit din in order for the conversion to be achieved and how long will it take if I have a great knowledge of Judaism ?
This is very nice that you would like to convert. It is not an easy journey, but if you are really serious about it, it will be very rewarding in a spiritual sense, and you will then be part of the Jewish people, and entitled to a Jews portion in olam haba.
If you want to convert to Orthodox Judaism in a realistic way, I would suggest that you consider moving to an orthodox community, in order to learn what it means to live as a Jew and not merely study Judaism. You will be able to get plenty of mentoring there. The two closest cities in Europe that I can suggest would be Manchester London or Gateshead in England. Or consider coming to Israel to study. If you would like to do any of these ideas, let me know and I will see what I can do to help you out.
Truthfully, if you really want to convert you will have to move to a orthodox community in any case. This is because it is very difficult to live as an orthodox Jew in an area that you are the only orthodox person, without a minyan kosher food, communal support, friends etc. and realistically it might prove too hard. Think about it, and you can let me know if you wish.