I think you must enable the ssh access in the qnap settings then connect to it with terminal and then run the permission commands.
For enabling ssh access and connection with terminal, you must advice some Qnap forum.
Hello
SuiteCRM would work on the QNAP NAS. In very short, you need to switch on the “web server” and the “sql database” (mysql/mariadb) in the Settings, install the phpMyAdmin App. Now you could copy the suiteCRM Files into the Web Folder on the QNAP NAS and start SuiteCRM. The database could be created with phpMyAdmin.