Let’s asume you want to copy them from localhost, in that case you can use “scp” command:
scp /www/music/* your_ssh_user@your_external_host:/var/www/strapi-project/public/music
Where /www/music/ is your local folder with all the music and /var/www/strapi-project/public/music is your remote folder where you want to copy it.
Same will work if you want to copy from a remote host to another remote host:
scp your_ssh_user@first_external_host:/www/music/* your_ssh_user@second_external_host:/var/www/strapi-project/public/music