Storage meaning the capacity left on the hard drive for Photos, Documents and Apps etc? Or memory meaning the RAM slots?
Click the Apple in the menu bar and click 'About This Mac'. Click 'More Info...' and click on the 'Storage' tab at the top. This shows you how much space you have left on your hard drive.
If you want to know how much memory (RAM) you have, click on the 'Memory' tab and it shows you the current amoount of memory installed.
Hope this helps
On an 'old' MBP, click on the icon on the left side of the menu bar and 'About this Mac' from the drop down menu. This will show you the RAM that is installed:
For theinformation on the internal HDD, click on the HDD icon on your desktop COMMAND I (the lettter I) and it will give you the capacity of the HDD: