If you are setting up an FTP server (I’m using vsftpd in Debian Buster), setting the umask is the way you get incoming files to “take” the right permissions.

For text files, I like the permissions to be 644, which is rw-r--r-- (read-write for user, read for group, read for the world).

To get this in vsftpd, uncomment this line:

local_umask=022