people are migrating to other city
People is a plural reference to "person". "City" is a singular reference to "Cities", the plural form of the word. You must use consistent numerical references. Singular references for singular statements, and plural statements for plural subject references. Points lost for grammar knowledge and word usage accuracy.
There is a widespread worry about related to this situation.
Prompt topic deviation. The original prompt merely referred to a question of the advantage or disadvantage of this topic. There was no worry nor debate about it. You will lose points for misinterpreting the original topic in your restatement.
In this essay I will going to prove my point.
Points lost yet again for not answering in the required format. Do you see this as an advantage or disadvantage? You need not use flowery words of wisdom, you need to be direct to the point and clearly responsive to the task question.
First and primary scoring consideration for the essay response has already failed at this point. It leaves the exam taker with very little leeway to pass the test. It will be next to impossible due to lack of grammar control, obvious lack of English comprehension skills, and incorrect opinion statement format. There is no sense in reviewing the rest of the essay since it has already failed to meet the minimum passing requirements.