thinking of downloading CC

Eileen,

I am assuming you are talking about subscribing to the photography plan (Photoshop CC + Lightroom CC).

As Simone explained, your photos are not kept inside Photoshop, Lightroom, or Elements. All the Library module in Lightroom and the Organizer module in Elements will do is maintain a catalog of your files. Your files are stored on your computer. It is just like the old-fashioned card catalog in a library. The catalog cards with the pertinent information on the books are kept in the drawers; the books themselves are stored on the shelves.

Are you planning to also store your photos in the Creative Cloud storage services? If so, you need to keep the following in mind.  Once you cancel your subscription, your storage limits in the Creative Cloud will be reduced to the level of the free membership. According to the CC FAQs, if you are above this new reduced limit, Adobe will give you 90 days to remove some of your photos to free up storage space. If you don’t comply you may not be able to continue accessing some or all of your photos. I don’t know if Adobe really enforces this policy. This is something that you would have to check with them.

Subscription to the CC version of Photoshop/Lightroom is very similar to subscribing to Internet services – no pay, no service. Once you stop your monthly payment, Adobe will pull the plug on both programs. They will still be on your computer but they will be disabled. Adobe won’t turn them back on unless you reinstate your payments. However, Adobe is a bit more generous when it comes to Lightroom. According to their FAQs, only the Develop module will be disabled; you can still access the Library and the Export module.

Also, another thing to keep in mind is that, depending on the nature of the editing you do in Photoshop CC, you will have a problem if you cancel your subscription and go back to use Elements. Why? Because not every Photoshop feature/tool is available in Elements. For example: Layer Groups. (A grouped layer will display a folder icon.) Layer Groups are used to organize your layers when you have too many of them; it is a very common feature in template files which consist of many layers. These layer groups can be collapsed and expanded. Unfortunately, you cannot do so in Photoshop Elements. This means that, unless you saved a copy of your files with the layers intact (not grouped), you will have to install an add-on to enable Elements to open these layer groups.

I am always hesitant to advise anyone when it comes to acquiring a given program. My standard answer is -- Download the free trial and test the waters. In this way, you will be able to make an informed decision, one based on your needs, interests, and budget.

It is also a good idea to check Adobe’s CC FAQs to get the answers you need straight from the horse’s mouth.  Creative Cloud | Common questions

I am also curious -- What are the things that you want to do that cannot be done in Elements?

Each and every version of Elements is based on a given version of Photoshop. Yes, some of the Photoshop features/tools are not available in Elements. However, Adobe has been steadily giving Elements features/tools which once were for Photoshop users only. Also, many of these features are "inside" Elements; they are just hidden, turned off. There are add-ons out there which, once installed in Elements, will turn on these features and they will do it for a very reasonable price such as: Elements+ ($12) and Elements XXL ($49.95)