Writing articles or content for websites is an art. You have to focus a lot of thing before you start writing. There are some tips that can help you to write your content better.
Before you make you content live on the internet or you are going to submit your paper, thing that must have to confirm that the content you written is 100% unique and not plagiarized with any of the other websites or documents. For plagiarism checking you can use many site like check-plagiarism, smallseotools, writersdrive, etc.
No one can say that he is a perfect writer, everyone is a human and humans always made mistakes. So there is a possibility of error in grammar and writing style. And to remove those errors you might have to use some kind of grammar check like grammarly, grammarcheck, check-spell, etc.