Will Boot Camp mess up my macOS?

Not if you do it correctly.

It installs Windows in a separate partition of the internal drive. You then may switch the startup drive between macOS and Windows.

You exit by restarting the computer from the macOS partition.

How to install Windows 10 on your Mac with Boot Camp Assistant

Installing Windows with Boot Camp

Below are several links to Apple support articles about installing Windows on your Mac using Boot Camp. Please read them carefully before embarking on your effort to run Windows on a Mac.

• Boot Camp - Apple Support
• Use Windows 10 on your Mac with Boot Camp - Apple Support
• Create an ISO image for Boot Camp from Windows installation media
• Use Windows 10 on your Mac with Boot Camp
• Boot Camp Help
• How to install Windows using Boot Camp - Apple Support

christianreal wrote:

Will Boot Camp ruin my mac? How does it work? How do you exit it?

Thanks, Christianreal

You have to ask yourself why would Apple present a Window capable Mac, with supporting software— to ruin your Mac?

Rebooting holding the Opton key is how you change the Boot Volume from Windows or macOS.

How to select a different startup disk - Apple Support

System requirements to install Windows using Boot Camp for ...

Install Windows 10 on your Mac with Boot Camp Assistant ...

There is a world of difference between using Windows via Boot Camp or Parallels. BC takes over the entire computer. There is no macOS running concurrently. You can use Windows or macOS but not both at the same time. BC requires a dedicated partition on the disk drive that is not resizable unless you first remove the existing one. Parallels provides concurrent operating systems and uses easily resizable pseudo-disks. Windows cannot boot from nor install on external drives. Parallels can boot and install Windows on an external or internal drive. BC is faster than Parallels but not much faster. BC cannot control the fan speeds often causing the computer to overheat. Not a problem in Parallels.

VirtualBox is free but runs slower than Parallels on a Mac. Parallels costs money but has a lot more features than VB.

Weigh the pros and cons before making your decision.

christianreal wrote:

Thanks, I appreciate the simple and fast responses. I ask because Parallels Desktop 13 isn’t working on Catalina anymore, and now Parallels 15 is making me pay.

Yes Parallels is a money sink.

This is what I use— You can try the VirtulaBox shareware. Oracle VM VirtualBox

It certainly is more convenient to switch desktops like any other full screen app—using a VM.

BootCamp is dedicated OS—one or the other, but not both at the same time— a reboot is required.

Bootcamp does allow for 100% of your computer power dedicated to the Windows OS as opposed to being shared.

If you elect to try using Bootcamp, then make sure you have a good verified working backup in case something does go wrong. You should already have regular system backups anyway.

christianreal Said:

"I ask because Parallels Desktop 13 isn’t working on Catalina anymore, and now Parallels 15 is making me pay."

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Seems Somewhat-Consequential:

What do mean "making me pay"? Is it prompting you to upgrade, and pay for it monetarily, or consequently? Contact Parallels and sees what they have to say on this upgrade/inaccessibility issue, making sure it is not a scam. The only consequence I could see is for having purchasing a new license key due to a macOS update.

christianreal Said:

"I just am looking for an easy way to get Windows and Mac on the same screen."

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See the below screenshots of my VMWare Fusion Windows 8.1 VM.

I use VMWare Fusion and have a Virtual Machine all the way back to Windows 2000. So, I'm not familiar with VirtualBox and Sheep Shaver. VMWare Fusion will run 32bit Programs on your VM while your Catalina macOS is running itself in the background. You would enable FTP to be able to share the items (drag-and-drop). I need to use Windows software - that's just the way it is :(

Screenshot 1:

My VMWare Fusion Windows 8.1 VM (With Personal Info Blanked Out):

Screenshot 2:

About VMWare Fusion:

It's not a scam. It's an upgrade cost to the latest version. Parallels has been charging upgrades since inception. You should check their website so that you know the answer. This cost is not due to a macOS update/upgrade.

The OP, apparently, doesn't understand this, either.

"Is it prompting you to upgrade, and pay for it monetarily, or consequently?" What does "or consequently" mean? Of course, it is monetarily. It's software for sale. What is the "consequence" of purchasing the software? Your sentence makes no sense.

I can understand the language errors you frequently make, if English is not your primary language. But if English is your first language, then you should read what you write carefully before posting it.

I'm not trying to be picky, insulting or mean-spirited. I see these errors too frequently in your posts. I think they need to be improved. I hope you will take the time to improve them.

Bootcamp will not run window 8.1 on Catalina.

As posted above—System requirements to install Windows using Boot Camp for macOS

https://support.apple.com/en-us/HT204048