Jinu makes a good point about paragraphs. Paragraphing is very important. See the IELTS Task 2 writing descriptors under the heading "Coherence and Cohesion"
Perhaps it is a formatting issue. Here is your essay reformatted with some punctuation changes. Let's see how it looks then!
Academic success is achievements in educational work. There are some of factors which play a decisive role in academic success.
First of all, it is a willpower. Any person in order to get something must have a willpower. In other words any students must be self-controlled. Secondly, a student must have a desire and aim. A desire means enjoying to learn something new and the aim to get a high education which are vital in order to get a stimulating and rewarding job. Thirdly, students who wish to excel at studies should be diligent and hard-working. It implies not to be lazy and do homework every day. The most important factor is not to miss lessons. Nowadays students are not so successful at their studies as in the past because of playing on the computer to much. Some even become addicted that drops out colleges and universities.
The great example of academic success can be attributed with great Russian scientist Lomonosov. His diligence and industry lead to his world known success. He was born in the family of an angler . At his time people of his social class could afford to send their children to study. In spite of it, at nineteen young Lomonosov decided to go to Moscow in order to satisfy his only patience to study. Upon arriving in Moscow , he entered the Academy falsely claiming that he is the son of the priest. Due to his diligence he became a scientist and founded the University which is now named after him.
To summarize, education is an integral part of the society. If a student is industrious and do his best in order to have academic success then he can become an important member of the society. At it has been proved that a good educated people are a driving force in country's economy
Now that it is in paragraphs, I would make some other changes.
In the Introduction, I would add another sentence, perhaps asking if there is only one factor or if there are many. Have a thesis sentence. Starting with a definition, like you did, is fine, but it's not enough. Say what your essay will do.
Here's one possible rewrite of your introduction:
What is the best way to achieve in school or college? Is there one magic factor, or does it depend on the person? In my opinion three factors play a decisive role in academic success, and in this essay, I will explain why determination, a clear goal, and hard work are so important.
In Paragraph 2, I would have a topic sentence. You could change the first sentence a little:
Although there are several factors which contribute to academic success, the first one is willpower.
Paragraph 3 is interesting. You tell a story/give an example of Mikhail Lomonosov, an 18th-century scientist, mathematician, writer and poet. There is a danger here that unless the example is very closely tied to the topic that the examiner will suspect that it is a chunk of memorized text, or inappropriate or tangential (not related to the task). I would suggest shortening the paragraph, showing why the example is relevant (why angler? why priest?) and generally making it more part of the essay.
In the conclusion, I would delete the first line and the last sentence. It's not the issue being discussed. Instead summarize the ideas in your second paragraph.
The conclusion could be rewritten:
To summarize, if a student is industrious and does his best to have academic success then he can become an important member of society. Willpower, the desire to learn, and plain hard work will help any student to excel in school.