The FTP user account used for automation should have "Read-Only" access if it only needs to download files.
If you aren't comfortable with coding, several "Set-it-and-forget-it" tools exist: Offers scheduled transfer capabilities. auto download ftp files
For those who need to process files immediately after downloading, Python is the best choice. Using the ftplib library, you can write a script that downloads files and then sorts or parses them. The FTP user account used for automation should