Follow this:

1. Open the Local Group Policy Editor.

2. In the left pane of Local Group Policy Editor, Click on Administrative Templates.

3. Under Administrative Templates, click on Windows components and select Windows Defender from the list.

Now, under Windows Defender, you can see an option called “Turn off windows defender”. Click on it.

Under Windows Defender setting, Click on “Disabled” then click on okay or apply. That’s it. you are done. There are several other ways to disable to windows defender in your computer. you may like to check this: How to turn off Windows Defender

Note: I am the author of this blog.