Hi there...
if you want to get high band score, just looking for
IELTS Writing Band Descriptions and you may know about your
task response, coherence and cohesion, lexical resources and grammatical range / accuracy and all of the criteria of band 7 are written in there.
I think your essay quite good , but just be careful with your punctuation because you use many commas
However, with its many uses, it can be a source of destruction or a life saving tool for humanity
...
This use of atomic bomb, which is a product of nuclear technology, has led to unnecessary
...
Another example, is that, nuclear technology has provided a more effective
..
but overall good