I took Dreamweaver’s basic fluid layout to begin with, since I was learning fluid layouts
@susannb If I understand correctly you are trying to learn responsive webdesign, and I don’t know your situation, but I think this is admirable, if not something to be underestimated. Not to discourage you, but I have seen too many people giving up over here after hitting a wall, thinking media-queries were too difficult. Well it can get complicated very fast, but you needs some tools to help you out. Since you write you are a visual learner (aren’t we all in some way or another?), be sure to get yourself familiar with Chrome DevTools, or an equivalent in another browser like the one in Firefox, if you aren’t doing this already. Drag your browser window around with DevTools open, and see what elements change at which breakpoint, and then look up that element that you want to edit in your stylesheet; again, if you aren’t doing this already.
In this stage of development it would be best if you could pair up with a more experienced webdesigner. Ideally someone who had access to the same files you were working on (have to look out for different versions, hence the Git remark from Beverleyh), and leave comments right there in the code. This can partly be achieved over here when you make small demo’s in, let’s say Codepen, but like you wrote, you have a complete website with multiple pages to consider.
I used what Dreamweaver gave me and fiddled with it from there.
Now it’s a good time to start thinking about how you would like to set things up, (also regarding my comments above) in stead of what has been assumed by some general template from a text-editor. This is also a chance to get specific and make the most of your CSS; like having reusable code and the cascade work in your advantage in stead of fighting it (specificity).