Welcome to TPG Community!
Thanks for reaching out to us and we'll be glad to help you out on this matter.
If you are trying to put emails on a specific folder, you may use the filtering option under TPG Post Office.
Once logged in, go to Settings -> Mail Filtering Settings -> Advance Filtering Settings.
Then you can put the Condition and Value of the email you wanted to put in a specific folder.
You can also refer to this Community Link as a reference.
Let us know how it goes, thanks and have a great day!