Исправьте ошибки в английском тексте и упростите его, если возможно. Пожалуйста!

I'd say you started fine but the end is utterly a crap.

Понимаете, это резюме не будет понято иностранцами, поскольку текст составлен на русском и затем переведён. Они не понимают наших оборотов речи.
Вот лучше бы пример Вашего саксессфул бизнес-плана и продемонстрировали. С бэк граундом в экономике Вы слишком круто - напишите economical basic knowledges inspired very distinctive perspectives.
Про свою викнесс -сразу удалите - они и без Вашей помощи знают каким "викнесс" мы тут все обладаем.
I'm working hardly at the department's team due to my own work-ability kindness -где-то так.
Хотя, с подобного все начинали -смелее и да поможет Вам б-г устроиться в загран конторе.

Подкорректирую... но это не proof-reading - сразу предупреждаю, дабы избежать нападок Сергея Петрова, который сам НИЧЕГО не сделал, чтобы на вопрос ответить!: -)

I started my education at A gymnasium when I was seven. I -- studied there 12 years. And now I'm A second-year student of AN economic school. I DON'T have ANY professional experience yet. --I think I fit best for this position as I have a strong economical background. I am a good team worker. My major achievement is a successful business plan, which I have done for my studYing. It was highLY assessed. I am good at learning foreign languages. I'm A hard-working and pragmatic person. My ADVANTAGES are RESPONSIBILITY, calmness, and determination. My DISADVANTAGES are confidence, curiosity, and self-doubt. I know THAT the company is now expanding and entering new markets. I know (THAT) you have some big (CONSIDERABLE) clients and a lot of international contracts. Your organization has a good reputation for building careers. I would take the initiative and establish good working relationships. I will work with interest and care. In (AS???) A manager, I look for A good communicator and adviser. HE\SHE must give clear instructions. I like to work in a team. It makeS the work more efficient. Working in a team will give us the team spirit. I HAVE not had ANY job yet, so I can't reply(???). I would stay in this company AS long as it IS possible. I hope to work here until retirement. Work is important FOR me, BECAUSE OF BEING useful and STAYING on a high social level. I expect A worthy salary, WHICH WILL BE equal to my efforts. I'll regret, but I will try to find the same interesting work. IT IS easy FOR ME to make AN unexpected trip, but IT IS difficult FOR ME to deny help TO my relatives.

Too many mistakes. The main fault is that you think Russian.Your Grammar leaves more to be desired.