At this time Windows 10 Home is no longer free, the program passed, there is one exception, Windows 10 for Assisted users is still available at the time of this writing for free if you qualify for this promotion.
https://www.microsoft.com/en-us/accessibility/windows10upgrade
If you had already installed Win 10 and gotten to the "welcome" screen on your mac then you could reinstall without registering it. Weather you are installing Windows 10 on a mac, a timex sinclair or, a loaf of bread it's still windows 10 and it still needs to be registered with Microsoft, so yes, it's a pay to use.
Programs like MS Word, Excel, Powerpoint, Creative Suite/Cloud, Blender, AutoDesk products, etc. If there is a PC and Mac version they can generally be interchangeable with one another seamlessly, and many Windows programs themselves can be run on a Mac with 3rd party software if you dont' want to install Windows, but you still need licenses for them and the software to run it. two of these products are
Wine https://www.winehq.orgwhich is free but a little complicated to users who don't like a bit of a technical challenge
and Crossover https://www.codeweavers.com/products/crossover-macwhich is built off wine, and its not free, but puts an interface on the program to take out much of that guesswork.
These products are only needed to run Windows Applications, but not needed to open files you made in MS Word, or Adobe Photoshop, or AutoDesk Sculptris 3D that were on a PC.
The majority of us rule against Mac Anti-Virus, but some volunteers here swear it is not a problem. My experience is I get to test it with multiple users in a corporate environment and see how it reacts. My personal findings from many years working in this field on both the Mac and PC side of it are if you run Windows on your Mac in it's own partition install a Windows AV solution on that partition but for the Mac partition don't bother. Windows virus do not attack Mac OS X, the most common Windows attacks would appear as gibberish to mac OS X and even if they are converted to run on mac they would try to re-write files that do not exist for Mac OS so their payloads would be ineffective.
• Mac AV solutions tend to cause serious problems with OS X, they can conflict with OS X, they tend to bog the system down when OS X is very equipped to deal with exploits and should be kept up-to-date with securities patches and OS X updates. Don't run Mac OS X like a Windows solution, its the quickest way to wreck the stability of the OS. OS X is astoundingly good at taking care of itself, Windows will do some things far better but keeping itself clean Mac is like a cat that stay indoors licking itself clean constantly and Windows is a dog digging a hole under the fence in a thunderstorm.
• Mac AV solutions from known AV developers lack the flexibility their Windows counterparts have. Just because some big name AV developer makes it does not mean they had capable Mac developers or they just didn't carry the code over from Windows and recompile for Mac
• Windows AV is 'light years' ahead of Mac AV in terms of support, testing, development and integration. Protect your Windows PC's by using AV developed for Windows not by using the mac as the gatekeeper and potentially crippling your OS to defend against Windows attacks that Windows AV can find with it's eyes closed.
• Mac AV has never been faced with an actual "in the wild" virus at this time and there is no way of knowing how any Mac AV solution would behave in the event one exists on the internet ("in the wild") that replicated itself. While this could change by the time I finish this sentence it is currently the state of Mac Virus by definition.
• The biggest threat to mac is actually fraud websites that tell you a virus is found on your mac and to call a toll free number to speak with an "apple rep" or a webpage that looks identical to Apple support or some apple site and asks for your apple ID/password, credit card, etc and AV is not designed to block these types of scams because thy are designed for you to do all the legwork and accommodate the scammers. Second to that are sites that direct you to phony Flash installs, you can find these on file sharing sites, torrent sites, sites that are in your best interest to stay the **** away from in the first place. Third is the misinformation presented by news services who hype an exploit to sell add space or generate click bait hits, much of what can affect Mac iOS and OS X has been grossly misrepresented by news reporters who make claims they don't have to substantiate or even understand. There are websites that will provide accurate assessments of potential Mac exploits, but news media outlets are not those bastions of truth.
• Malware and Adware exist for mac, but no where near the numbers you find for Windows. I do recommend the Malwarebytes for Mac which is developed by a frequent contributor and knowledgable member of this community, this software is free and it will remove adware/malware it is aware of, it does not protect you against going to a compromised site or more often a site that has no scruples against trying to defraud you in the first place.
