There are a few ways to exclude certain files/folders from being scanned by Windows Defender.
The first way is to adjust the security baseline settings in Windows Defender Security Center. You can use the Settings > Exclusions feature to choose which folders, files, and file types you would like to be excluded from getting scanned by Windows Defender. You can add and remove items to the exclusion list as needed.
The second way is to adjust the Group Policy settings for the computer or domain. You can select these policies to configure the exclusions on a local or domain level so that all computers have the same settings. This can be done by using the Windows Group Policy Editor (gpedit.msc) and navigating to Computer Configuration > Administrative templates > Windows Components > Windows Security > Antivirus and configure the antivirus exclusions that you want to be applied.
The third way to exclude specific files or folders from being scanned by Windows Defender is through the registry. You can do this by opening the registry editor (regedit.exe) and navigating to the following registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Defender\Exclusions. Then you can manually add or remove the selected files and folders to be excluded from Windows Defender scanning.
Finally, the fourth way to exclude certain files and folders from being detected by Windows Defender is to use a third-party utility such as the Windows Defender Exclusion Tool (WDET).This is a free utility developed to allow system administrators to easily and quickly manage all the Windows Defender exclusions, both on a local and domain level. With WDET, you can add and remove any item(s) to the exclusion list, create your own custom lists to exclude multiple files or folders at once, and manage the various levels of exclusions.
No matter which method you use to exclude certain files and folders from being scanned by Windows Defender, it is important to remember that Windows Defender still runs background scans and will report any malicious activities or incidents. So make sure to use these methods responsibly and update Windows Defender regularly to ensure that your system remains protected and secure.