помогите пожалуйста, проверьте на наличие граматических ошибок. . (англ. яз) очень нужно. за ранее спасибо

1. Первое предложение очень конфузное, к сожалению ...давайте я не буду говорить, что там неверно, просто посмотрите на мое:
In my high school at the beginning of the grade nine year each student has to look for a two-week internship, where he delivers his placement at the end of the school year.
Я не уверен, что глагол "to had" оправдывает там себя, вы же дальше пишите ..."We should choose a job" и "I've chosen a travel agency..."

2. We should choose a job, what we maybe would like to do later = We should choose a job that we maybe would like to do later.

3. In my class there were many different occupations that the students wanted to choose or have allready chosen.
students - мн. число, артикль на надо
allready = already

4. Some will spend this 2 weeks in a tax office, some in kindergarten, but I´ve chosen a travel agency...
Числа надо писать прописью - правило такое есть, что пишется числом, а что прописью. В вашем случае прописью, а значит везде, где 2 - надо писать "two" ...:))
this 2 weeks = these two weeks

5. At first I thought it's a easy job = it's an easy job запятая where you just sit on PC = where you just sit at your PC and various hotels - непонятная мысль "and various hotels"? ..
Может так: At first I thought it's an easy job, where you just sit at your PC, pick out the best looking hotel of all that you found and sell it to the costumer.

sit, pick, sell - это называется "Maintain consistent verb tenses"

6. by head - наверное "by heart" вы хотите сказать, типа наизусть?
You have to know country abbreviation and three letter airport city codes for major airports around the world by heart точка, остальное мне кажется, что лишнее, иначе мысль неясная "for using some special systems." или так: "or using some special systems" точка :)

7. Should anything go wrong = If anything goes wrong,...
wright time - это надо понимать, как неправильное время?
If anything goes wrong, especially the wrong booking time, or letter of the name is spelled wrong on the booking, or any single error - it may cause the traveler to be not approved for the flight.
couse = cause

8. I had a lot of fut = I have a lot of fun
this 2 weeks = these two weeks
to made this profession as travel clerk = being as a travel agent.
Being as a travel agent, I have a lot of fun these two weeks.

9. It was also very nice that my manager had confidence in me точка, дальше идет другая мысль ...или двоеточее:

10. I could bring the passports to the office, could write myself visa applications and was able to sort the bills.
passports - мн. число (без артикля)
write myself = write by myself
bills - мн. число
could - не надо повторять.
and was = and I was
I could bring passports to the office, write visa applications by myself and I was able to sort bills.

или просто "and sort bills" имеется ввиду, что I could bring passports ...write visa ...and sort bills, но если вы хотите сказать "was able to" то говорите "I was able to"

11. This job can be something for me, - режит слух "can be something"
could be mine ...
becouse = because
talk with clients = talk to clients
those = them
This job could be mine, because I have very much fun at the office, talk to clients and prepared them with a good travel pleasure.

Надеюсь, что вы разберетесь! ? Если что не так, спрашивайте. Удачи!! !

дайте русский вариант некоторые вещи не понятны, я лучше сама переведу вам, можно в личку=)