Hello:
I work for an online proofreading and editing service. Please see my profile for more info. I won't revise your whole essay here, but I will show you the changes I would make in your first two paragraphs (which I have combined into one).

To The Selection Committee:
I have lived my whole life in the same country, in the same city, so my dearest dream is to study abroad after I graduate high school. I love my hometown but feel a strong need to discover new cultures and gain new experience. Studying at the English-taught bachelor's programme in Economics and Business, at the University of Amsterdam will provide me with the knowledge and change of scene that I crave.

The beginning of your motivation letter is basically sound, but please pay careful attention to the changes I have made.
1) Salutations for a motivation letter (or anything other than junk mail) should never begin "To Whom It May Concern". Either do a little research to find out the full name and title of the contact person (Dr. would be the most likely title in the U.S.) or use my salutation (which is acceptable for this type of program which--in the U.S.--usually has a committee reviewing applications). Also, a business (as opposed to personal) letter salutation always ends in a colon.
2) I made your sentences a lot more direct and eliminated unnecessary words like "hereby", which is old-fashioned and should be used only in official proclamations.The program and university you are applying to should be part of your concluding sentence in the first paragraph.
3) Avoid the word "foreign" in this context. The country and the language are not foreign to the people to whom you are addressing this letter.
4) Try to include either in this paragraph or the one right after it why you would be a great addition to this program. Make the letter less about what you want and more about why they should want you.
Good luck and take care.