After following the instructions to create a "Batch" and it was time to upload my work using FTP, but my work after uploading could not be seen anywhere, whether it was an error or it was not visible and was waiting to be reviewed or there are other methods?
First thing to check: have you applied for the special program that allows you to submit PSDT files, and been accepted?
maybe that's what I don't know.
How do I join the program, is it still possible now?
There are a lot of special rules applying to templates; one reason Adobe require you to apply is to make sure you design to their rules - otherwise you and they could both waste a lot of time. Start here, which includes the requirements and, if you feel you can meet them, a link to how to apply. https://helpx.adobe.com/uk/stock/contributor/help/design-template-requirements.html