I am currently setting up Parse Cloud Code and I have gotten to the final step which is to deploy the main.js file but when I do this it just opens the file in Adobe Dreamweaver?
As far as I understand from your question, you want to deploy the main.js file to the Parse cloud. The problem that you face opening in Adobe Dreamweaver is related with your computer where you configure the file open with the Adobe Dreamweaver.
The answer to your question is; as detailed in Parse Cloud tutorial, first you have to install Parse command line tool. This tool enables you to manage your code in Parse cloud. Then you can use "parse new" command to set up a cloud directory where you have to replace the main.js file with your own. Following that "parse deploy" will deploy your js file to the Parse cloud. You can find detailed information in tutorials Parse Cloud. Hope this helps.
Regards.