I use both Google Drive and Dropbox. Dropbox is simpler as on a PC with Dropbox installed and running you just start it and anything that you save to the folder on your PC designated Dropbox will go to the cloud and be there to retrieve on another computer with the Dropbox software installed and running signed into that account or with a Dropbox app on a phone or tablet. Dropbox is better for opening with your own software like Word. You also have the ability to just sign into the Dropbox website and see your files.
Google Drive has evolved into a pain. Google Drive now wants to open everything in its own cloud-based MS compatible software.
Both are free - try both and see which works best for you.
