So I have a macbook air and it is stuck on the version 10.8 and I have checked app store for updates and I clicked on the apple logo and clicked software updates. It says I have none available when clearly there are newer versions out there. This prevents me from downloading some things because they require my version to be 10.10 or higher. Please help.
You need to check inside the featured section of the Mac App Store because new versions of OS X do not always show up in the updates and you have to purchase it (the last three versions have been free) from the Mac App Store and install it. If 10.11 is okay, than that is still available in the App Store. It should be in the featured section or if you search, you will have no trouble finding it. It is only possible to get 10.10 if you purchased it while it is still available, in which case it would be in your purchased tab.