Unfortunately what you're doing is going to take a lot of effort / very difficult to do if you're just starting off. When designing for both web and mobile it's best to start off thinking about both in mind. There isn't a better program than Dreamweaver for what you're doing, however you might want to check out something called Zurb's Foundation.
Zurb's Foundation which you can find
here. It will automatically scale images and boxes to fit to mobile devices once the resolution crosses a certain reduced size. It's extremely handy for what you're attempting to do and I highly suggest taking a look at it.
Best of Luck
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remove things in html from css
