Honestly, setting up email within Microsoft's Mail app couldn't be easier. Launch it (either via the Start menu or via Cortana) and then simply add an account. You'll need to type in your email address and password, but after that you should find Mail reaches out and grabs what it needs. If you'd like, you can even add multiple accounts and switch back and forth.
About the only tip I'd recommend is clicking the "More" link in the left-hand list of links. That opens up a number of different folders in which to store your email, as well as the Clutter folder, which is Microsoft's modern equivalent of the Spam folder, hiding emails that aren't quite junk, but aren't important, either. You may also want to explore the Settings menu (in this app, it's a gear icon in the bottom left corner).
The Store: Go get Office
Last but not least, you'll want to grab a copy of Microsoft Office. You have two options: pay for a full-fledged copy of Office 365--which will require you to pay $70 per year for Office Personal--or the much simpler, cheaper route: Word Mobile, Excel Mobile, and PowerPoint Mobile. All three are free, and available via the Store app.
Microsoft's Store is a home for, quite frankly, a lot of mediocre apps that you don't need. What you should do, however, is type "Word Mobile" into the search bar, download it, and do the same for the other two apps. Word Mobile doesn't have all the features of Office 365, but it has enough to satisfy the casual user.
That's it! Please feel free to wander through the rest of Windows 10.
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