Newby didn't know to set for phone and tablet

Hello, I spent quite a few hours getting the site to look just how I wanted it on a PC! But when I opened it on the phone, of course it is a mess. I tried rebuilding by going with phone view, but it completely messed up my website build! Luckily, I was able to undo most of the damage I did. Any way to fis it for phone use without messing up my build? I read a few threads that said it would not mess up my desktop version, but it sure seemed too! Help please. I also really have trouble moving modules. Would the block builder be worth it. Especially trying to line up text with images. Is there a way to do that easier?