1. How do I make every new file I make have its default syntax theme (and type) set to PHP? (not it's plain text)
Can't do it right now, or at least I am not aware of this feature... Good news is that:
it is possible with a plugin. Hook into onNew(view) event and set syntax as PHP, shouldn't be too hard (but then again you being new to sublime I guess it makes it hard

)
2. Is there a way to preview PHP files (just like Dreamweaver's F12 preview thingy) with Sublime?
If I recall correctly f12 in dreamweaver previews current file in default browser... if that's the case yes you can do that in sublime, just right click on the file and select "open in browser", in sublime *almost* everything is configurable so of course you can bind that to f12 if you wish so, the command is
openInBrowser put that in your user keybindings
- Code: Select all
<binding key="f12" command="openInBrowser">