iMac infected with virus that creates hidden windows partition, won’t boot from USB or internet recovery

You can't even begin to believe how far off into left field you are. I'm not even sure where to start, there's so much wrong with your statements.

Let's start with the massively illogical argument that you think you have a Windows virus.

1. You don't have Windows installed.
2. A Windows virus can only run in Windows.
3. So, um, exactly how is a Windows virus running on a computer that doesn't even have Windows on it?

Check our what I see from disk utility in the fake Catalina base system install when I try to boot from internet recovery.

That's the Recovery partition the Mac boots to when you choose to startup in Recovery Mode (Command+R). It shouldn't even be visible. That you managed to make it visible is a good sign you destroyed it. Good job.

Your next couple of posts and screen shots only repeat that you think a hidden disk image that's supposed to be there is a problem. It's not. Except you now made it one by wrecking it.

Here is some more photo evidence of a program that I didn’t install that can now access my computer.

Every single Mac has that function. It's proof of nothing.

5 minutes from booting the computer I have 115,000 console messages.

Whoop-dee-doo. Every computer running Unix will pile up that many messages, or more, in that amount of time.

Except I’m not running windows and I didn’t install windows on the computer, I installed Catalina.

I didn’t install windows on the computer, the virus did.

Do you have any idea - at all - how ridiculous that is? You're describing a thoroughly impossible loop.

1. You don't have Windows installed.
2. You somehow have a Windows virus anyway.
3. The virus, which requires Windows to run, installed Windows. Something you couldn't have possibly missed happening.
4. Except, it's impossible for the virus to install Windows since it requires the presence of Windows to run - at all.
5. Go back to step 1 and keep repeating this very literally impossible sequence.

the fake disk utility and fake terminal

Wow. Just wow. Where did these "fake" utilities come from? Saturn? There's no penetrating this much utter nonsense and paranoia.

I sure won't be wasting any more time on this topic. I may continue reading it for the fantasy entertainment value, but nothing else.

Normal, in terminal execute this command...

diskutil info -all

Down on the list you'll see...

  Device Identifier:    disk0s1

  Device Node:       /dev/disk0s1

  Whole:          No

  Part of Whole:      disk0

  Volume Name:       EFI

  Mounted:         No

  Partition Type:      EFI

  File System Personality: MS-DOS FAT32

  Type (Bundle):      msdos

  Name (User Visible):   MS-DOS (FAT32)

  OS Can Be Installed:   No

  Media Type:        Generic

  Protocol:         SATA

  SMART Status:       Verified

  Volume UUID:       0E239BC6-F960-3107-89CF-1C97F78BB46B

  Disk / Partition UUID:  14F65236-8282-4FEE-A916-01189FD6ADA3

  Partition Offset:     20480 Bytes (40 512-Byte-Device-Blocks)

  Disk Size:        209.7 MB (209715200 Bytes) (exactly 409600 512-Byte-Units)

Based on the report the only thing wrong with your iMac is that is was the slowest iMac that was offered by Apple at the time of purchase: 8GB of RAM and a 5400 rpm hard drive. No wonder it's slow.

Therefore when using that computer have as few apps open at one time as possible.

soundboy13 wrote:

Everything is far from normal

Everything is completely normal.

why does my 500gb drivd format to 465gb

It doesn't. You are looking at free space:

Container Free Space: 466.9 GB

It is only 467 GB because you have used 33 GB for other data.

then immediatly show it’s formatted to 500gb and create a windows partition?

Modern Macs aren't much different than Windows machines. They run the same Intel chips. They can boot Windows. The low level hardware-support volumes are in Windows format because that simpler format is something that the booting firmware can understand. Once the system is up and running, it uses the normal Mac booting volumes.

It also remembers my previous wifi network and password when I install the OS from ethernet on a fresh format, and when it boots I'm connected to wifi without having to enter my SSID and password.

Completely normal. This information is stored in the parameter RAM. It is a convenience for updating your system and installing firmware updates when you only have a WiFi connection.

soundboy13 Said:

"iMac infected with virus that creates hidden windows partition, won’t boot from USB or internet recovery: [...]I can see a 40GB windows partition, and this is immediately after formatting the computer and booting into OS Catalina for the first time.[...]"

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To Emphasize on my Previous Reply:

After you delete the partition, be sure to format the Hard Drive - If using Catalina - use APFS as the File System (AKA: The Format Type).

soundboy13 Said:

"when it boots from internet recovery, shouldn’t it go directly into the recovery mode. If you watch the video you will see where it shows an apple symbol and loads the recovery mode after that."

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You are welcome.

Thank You for the Video!

It is Doing it as intended - what it is in fact doing is downloading and then encapsulating all the install files, readying itself for installation. Internet Recovery Mode is its own method - it does not go into Recovery Mode, after going through the download. View: "If you can't start up from macOS Recovery"at this link: About macOS Recovery

Erase the Drive:

Are you concerned with losing data? If not, just erase the drive, setting APFS format. Once formatted, see if all 500GB is shown (it might be a few GB less, because the drive has its own files on it).

As for the other 50GB:

Is the other 50GB shown after performing an erase? It would read maybe 498GB.

soundboy13 Said:

"But what I don’t understand is why is the data not shown as taking up space after you format the drive?"

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For Reverence:

I. APFS Formatting:

Go Here: Add, delete, or erase APFS volumes in Disk Utility on Mac

II. Opening Terminal in Recovery Mode:

1. Boot: into Recovery Mode
2. Click: Utilities Menu
3. Select: Terminal

I have reinstalled a few times now and I keep having the same issues, so this time I formatted with a GUID partition, but once I install Catalina it seems to be automatically formatted as APFS

That is the correct way to do it: GUID. Catalina will reformat automatically. that is normal.

right after it format then it shows it’s 500gb. This is normal? Shouldn’t it show the used space?

formatting erases the drive which means there will be nothing on it. it is normal.

You are seeing problems where there are none.

At this point, I recommend that you contact Apple support for further assistance.