I'm hoping to upgrade to a computer which doesn't have Microsoft software. Is there anyway that I can still take part in workshop if I don't have Word?
Sure, use Open Office or Neo Office, both free and open-source. You will probably have compatibility issues that will lead to wonkiness, but they are much better than they used to be, and your comments will get through.
I will say, though, that I'm a strong advocate of purchasing Microsoft Word if you're serious about your writing. The vast majority of publishers will request a .doc or .docx file in your submission, and I've learned that, even if you can save or convert to that file type from your preferred software, it's a really good idea to glance it over in Word before submitting it.
I have an apple and use Pages. It can make .doc files, but is this good enough? I mean, a file type is a file type, right?
.doc that isn't from Office can be a little wonky, but mostly yeah.
Check out Amazon or Ebay for older copies of Word.