Language defects:*There is
AN increasing number
*staffs does NOT take s in this context
*that
A knowledgeable person
*some right
S which
ARE out of reach OF people
*Finally, somebody applies for a college to have new experiences > Finally, ONE MAY APPLY for a college to have new experiences. You can also express it in many other ways, however, at any rate your way of saying it is defective. You can't use SOMEBODY in that way, dude.
*study
AT university
*Inconclusion>In conclusion
Structural defectsYour three body paragraphs, starting with firstly secondly and finally, are rather fine. Your main structural mistakes lie in the first and last paragraphs, the most important ones, ironically. You have not developed the thesis sentence very well in your opening paragraph. It should have introduced and touched the points in your body paragraphs. though your do this task, it is not complete and not well-formed. I think a 1st paragraph like this scores full in this regard:
There is an increasing number of people who attend university and college every year. The reasons behind this fact can be numerous. To name some, people may attend university and college for qualifying for a favorite job, gaining social status through education and achieving life experience.
I'm sorry to say this bad news that your writing can't get any more than 20 IMO. 5 is deducted for your structure and 5 for your defective use of language: grammar, wording,... . But all in all, if you are not native and as you said it's your preliminary work, there must be great room for improvement.
Gud luck
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Ambition, Motivation and Determination: the three "tion"s that lead to PERFECTION.
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