The conclusion paragraph, like any other paragraph, needs a point or topic sentence. The point of the the conclusion paragraph is the answer to the essay question. You already stated this as the first sentence of your introduction paragraph as a bold claim which you then needed to persuade your reader was true. This time you are stating it as the logical and (hopefully) irrefutable outcome of all the evidence and arguments you have been putting forward in the essay.
For example, if the essay question was "Children are active and creative in their relationship with new media technologies. Discuss." then the first sentence of your conclusion paragraph might be "In conclusion, we can see that children can certainly be active and creative in their relationship with new media technologies"
The remainder of the conclusion paragraph will then expand on and elaborate the point or topic sentence (just like any other paragraph would). One way to do this is to succinctly restate the key points you have made in your essay so far. This is a perfectly valid way to write a conclusion paragraph.
A stronger, but more difficult way, is to attempt a synthesis. I like to think of synthesis as being a bit like making a cake from scratch. You start out with flour and eggs and butter and sugar and maybe some other ingredients like flavourings or raisins or chocolate chips. But after you have mixed and bake them, they turn into something new and unexpected - a cake. Synthesis is about putting together the ingredients in a new and original way so that your conclusion doesn't simply re-state the points you have made, but provides a new way of looking at them. Like baking a cake, it requires you to be a little bit creative.
It sounds hard, but it doesn't have to be so hard. One way to attempt a synthesis is to ask yourself "Can all of my points be collected into categories?". For example, do you have a number of points which are in favour of a certain view and some other points which are against? Or can your points be grouped into e.g. internal vs external factors, or alterable vs unalterable factors, or arguments based mainly on direct evidence vs arguments based mainly on theoretical considerations? Or maybe your points break down into three different categories, or even four (although it is harder to have many categories if you only have a few paragraphs as in a typical undergraduate essay of 2000-3000 words).
Or perhaps you notice that the essay question has different answers depending on how you look at it. Maybe you can argue that girls are creative and active in their use of new media technologies, but not boys. Or that wealthy children are, but not poor children. Or that children in the global north are but not in the global south.
Whatever your conclusion, it shouldn't come as a complete surprise to the reader. You should have already stated your answer to the essay question in the introduction paragraph, and your paragraphs should have been structured so the reader always undertands where you have gone and where you are going. The conclusion must never contradict the essay, but sometimes it might put a delightful new spin on it.