how do i access my dropbox, on pc i can access through this pc folder and have as a favourite folder
After installing dropbox on a Mac, your dropbox folder will be accessible right from the menubar icon it installs. You can also open Finder and it will be listed on the left with your favorites. Lastly, if you open your home folder which normally is named after you, your dropbox folder lives there.
As for opening tabs in Safari everyone else covered that pretty well but another simple way to open a new one, say if you just want to open one to search for something or whatever while retaining others already open, there is a little plus sign to the right side of the open tab or tabs you can click which opens a new tab for you.
As mentioned above too, the introductory tutorial pages are well worth a read at first. I found them quite helpful when I was transitioning from Windows a few years ago.
On a happy note, after the initial confusion you are soon going to find working in OS X to be a very natural and intuitive experience once you make the initial adjustment to how it does things you knew how to do in Windows.
One of the really wonderful things about the Mac world is all the great specialized apps that are available which I never found to be the case with Windows. You can always ask in the relevant forums here for advice on best apps for various tasks when ready to explore that. For fun, be sure to check out the Mac App Store and just peruse some of the possibilities there. I have found I could never imagine going back to Windows now myself. I could not get all the stuff I now take for granted here in Windows.
Enjoy your new Mac!
