ielts essay pls look at it :) and tell does it make sense at all?

Some people believe that if there were only a few languages in the world we would be able to communicate much easier. I fully agree with this point of view.
First of all, if there existed only 3 or 4 main languages, for example, the language barrier probably would be gone forever. Which would be a great relief to the human race.
For instance, nowadays if a person, who comes from a country with a lesser-known language, goes to to another country, and has no ability to speak other more popular languages, he wont be able to converse or ask, even about basic things.
On the other hand if this situation changes in the future, there wouldn't be any problems to communicate freely.
Nevertheless, as far as I am concerned, it will take a lot of time for this to happen. Many generations will have to change, one after the other, and there time needs to pass until people will get used to this new kind of lifestyle.
But looking at it from a different angle, a great deal of languages will dissappear, and this will happen to the countries with not such a worldwide language. Of course this will cost many piaces of their history, which will not be liked by everyone, but we have to take an honest look about this because more and more people learn so called international languages and most often the English language, because nowadays to be good at whatever you do ,you have to know at least one foreign language.
In conclusion I think that the the world needs only a few kinds of languages, which is going to help mankind to prevent  missunderstandings and complicated connections.

Ok, I'm going to be pretty tough with this one...

IELTS essay - please look at it and tell me if it makes any sense at all? :)

I realise this is just a note, but be careful with capitals and abbreviations. Tell needs someone to be told (tell me).

Some people believe that if there were only a few languages in the world, we would be able to communicate much more easily. I fully agree with this point of view.

Using were instead of was is our subjunctive (imagined/hypothetical) mood. You need this for the second conditional, ie. unlikely hypothetical situations.

You have an action here (to communicate) so use an adverb (more easily).

First of all, if there existed only three or four main languages, for example, the language barrier probably would be gone forever, which would further lead to a great relief among human beings.

Again, you have second conditional so use the subjunctive mood. In this case, it means making the action in the "if" clause simple past: if there existed...

In proper English, please write out numerals as words.

For instance, nowadays if a person, who comes from a country with a lesser-known language, goes to to another country yet has no ability to speak other more popular languages, he won't be able to talk or even ask about basic things.

I cut out the commas around "who comes from.." as this info is important to the sentence and tells us which person we mean. If you can remove this relative clause and the sentence still makes perfect sense, then add the commas.

Make sure you add apostrophes to contractions such as won't. Wont is actually a different word.

On the other hand, if this situation changes in the future, there won't be any problems in communicating freely.

First conditional (if... changes, there won't... - simple present, simple future). Use this for likely situations, or even just to show you think the situation is ideal.

Also, an adverb again (freely). Note: to communicate, and in communicating.

Nevertheless, as far as I am concerned, it has to take a lot of time until this is going to happens. Many generations would have to change one after another and there need time needs to be passed until people getting used to this new kind of lifestyle.

When an action stands as a time, use present form. "It has to take a lot of time until (when?) this happens."

As a theoretical situation, add would.

Time does the passing, so no need for passive voice. Note that another "when" clause follows.

But Looking from a different angle, a great amount of languages would disappear and this would happen to the countries without such an international language. Of course this would be at the cost of much many piaces of their history, which will not be liked by everyone. However, if we ought to take an honest look at this because-more and more people learn so-called international languages, and most often - English. language,This is mainly because nowadays to be good at whatever you do, you have to know at least one foreign language.

Use such when a noun follows, and so when only adjectives follow. This is such a difficult test! This test is so difficult!

The last half was very messy. The main cause was that you tried to write one long sentence instead of ordering your thoughts properly. If in doubt, write short sentences first, then see if you can put a couple of them together.

Be so very careful with the word look. You take a look at something.

In conclusion, I think that the the world needs only a few kinds of languages, which is going to would help the humankind to prevent from avoid misunderstandings and complicated relationships.

Once again, use would because it's hypothetical. Going to means it is already happening.

The word mankind is falling out of use as we make English more gender-neutral.

In general, this is pretty good. Just watch the occasional spelling and (more complex) grammar forms. Also, since you have a word limit, if the disagreeable point of view is easier to write, then I agree it's better to do that. ;)