No windows defender after installing windows

I'm not referring to a USB disk. Let me be more explicit.

I assume you were installing Win 10 to an internal disk.

Win 10 for most users should be installed to unallocated space on an internal disk.

When you said there were no partitions. do you mean there were no partitions on your internal disk?

Kindly confirm: did you delete all existing partitions comprising Win 10 on your internal disk when you installed Win 10 to said internal disk?

Kindly confirm: did you therefore install Win 10 to unallocated space on said internal disk?

2 please would you explain what method you used to check that you did not have windows defender installed.

I looked for the file after guidance on the internet. I checked the registry for windows defender folders and they where missing.

3 Please enter this in File explorer's address bar and either post a list of its subfolders or post a screenshot of what you see there.
C:\ProgramData\Microsoft\Windows Defender\Platform

Not sure how to do a screen shot but I get "This folder is empty"

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I assume you were installing Win 10 to an internal disk.

Yes

When you said there were no partitions. do you mean there were no partitions on your internal disk?

Yes

Kindly confirm: did you delete all existing partitions comprising Win 10 on your internal disk when you installed Win 10 to said internal disk?

I installed windows 10 on drive C: I did not have partitions before installing windows 10.

Kindly confirm: did you therefore install Win 10 to unallocated space [/B]on said internal disk?

Yes. Please note also, that I'm unable to get updates.