NT SERVICE\MSSQLSERVER cannot be found to add as user for file permissions

I need to give the NT SERVICE\MSSQLSERVER account permissions on a folder to be able to move and rename some files. I'm getting an access denied error. From the SQL Configuration tool, the services is set up like the below image. What else has to be done to make this appear as a user account?

What else has to be done to make this appear as a user account?

Nothing. And it doesn't matter what your service account is. The SQL Server service always has privileges assigned to the per-Service SID "NT Service\MSSQLSERVER".

If the files are on the SQL Server, just add permissions for this account:

And if the files are on a remote share, give the permissions to the machine account instead, eg \$.

StackExchange Database Administrators Q#291473, answer score: 5