With your Office 365 subscription, Word checks for spelling, grammar, and clarity when you're working in a document. Word autocorrects a lot of mistakes for you, and if it's not autocorrected, you'll see a squiggly line appear under misspelled words, a double underline for grammar, and a dotted line appear for issues with clarity.  

For more tips like this, check out the working remotely playlist at www.youtube.com/FoetronAcademy . Also, if you need any further assistance then you can raise a support ticket and get it addressed.