How to Share drive files to the trusted domain?

Let the users share only with certain organizations outside of your business or school. Add the organization's domain to your allowlist of trusted domains, and then choose sharing settings for your users.

Allow external sharing with only trusted domains:

Step 1: Sign in to your Google Admin console using admin.google.com

Step 2: Go to Accounts -> Domains

Step 3: Under Domains -> Select Allowlisted domains

 

Step 4: Click on Add domain and Enter the domain name you want to make it as trusted

Step 5: Click on save

Step 6: Go to Apps -> Google workspace -> Drive and Docs

Step 7: Select the Organizational unit and click on Sharing settings 

Step 8: Under sharing options ->  Enable ALLOWLISTED DOMAINS 

Step 9: Select the allowlisted Domain.

Step 10: Click on Save

Note: Trusted domain is the external domain for which you want to share the drive file, to do that we are adding that domain to the trusted domain section.

For your reference find the article: https://support.google.com/a/answer/6160020?hl=en