Hey honey179,
I understand that you're looking to purchase a new MacBook Pro and you want to know the difference between a memory and storage. I'd be more than happy to explain the difference!
The storage would be the amount of space you have on your Mac. The more storage you have, the more files, videos, etc. you can save on your Mac.
The memory or the 'RAM' plays part of running your applications and the operating system. The more memory you have, the more applications you can run at the same time. Basically, if you're looking to multitask with a lot of apps, you'll need a sufficient amount of memory on your Mac.
I hope this helps and let me know if you have any additional questions!
Warm regards.