Your Title and question are quite different, so I will addres the question.
To see if you are up to date on your OSX, click on the Apple logo in the menu bar (upper left) then from the menu that drops down click software update. This should bring up a progress bar as it looks thru your system for items that may need to be updated. After it runs, it will come up with a window of things that need to be updated, or it will come saying that your software is up to date.
If it comes up with a long list of updates, it is best to do them one at a time, just uncheck all but the one you want to install, and clcik install. After it installs software uodate will run againn, just repeat the process untill there are none left. Message your software is up tp date)
Hope this helps.