If you have come from a PC, save yourself some function frustration and use an ordinary 2 button/ scroll wheel mouse when you can - wireless or wired, it doesn't matter.
Macolytes love their keystroke combos (and you'll learn them in time) and the trackpad is nice, but if you want familiar access to right-click functionality and scrolling, a mouse is still the way to go. And no need to blow the big bucks on a cool looking Mac one. The OS will see and use a regular one exactly as you would expect.
Further, if you're coming from PC (and maybe you've used older versions of Word, etc), you may want a familiar-looking Office Suite. While Apple's own iWork Suite (Pages, etc) syncs with iCloud - if that's important to you - you may find its layout, frankly, bizarre and it's proprietary file system nearly worthless if you plan on creating and sharing documents with others. Short of the online options (like Google Drive or Microsoft Office 365), if you want an onboard office suite, I'd recommend the free LibreOffice product -
https://www.libreoffice.org/download/libreoffice-fresh/
You can set it to Save in the Microsoft format (Word, Excel, etc) of your choice by default and its rendering of existing files is pretty accurate.