Create custom Attach Field

I am trying to add a custom attach field to the customer form. The idea is that when one creates a customer they have to also upload some pdf form.

The system creates an attach button but no way to browse to the file location in order to upload the form.

Kind explain how one should go around that.

I have tried many ERPs but find ERPNEXT to be the most well rounded of them all. Congratulations on a wonderful open-source ERP

Ok, Ignore this question. I realize one has to save a customer first before uploading a form. The attach works perfectly.