Apple Numbers is similar to Excel, Pages is similar to Word and Keynote is similar to PowerPoint. In most cases the Apple software can open the Microsoft counterpart, so Numbers can open an Excel document.
I use Pages and Numbers for business. I have them on my Mac and my iPhone. Any document that I store on iCloud can be opened and edited on both a Mac and iPhone. If you own a Mac, you get 5GB of free storage space on iCloud.
To setup iCloud:
Go to the Apple icon in the upper left corner > System Preferences > iCloud. Setup is easy.
After that you can select the items that Sync on your Mac, iPhone and iPad. I have everything checked except Keychain and Back to my Mac.
Now the cool part, if you add a Bookmark in Safari on your iPhone or iPad, it's now on your Mac and vice versa. Make a Calendar change, it changes on all instantly. The same is true with Mail accounts, Notes, Reminders, Photos and Documents.
Find my Mac will locate you wireless computer and IOS devices like iPad and iPhone. It will show you there location on a map.
To see what's on iCloud, you can access it in https://www.icloud.com
You can add documents to iCloud simply by dragging them from Finder.