FTP to SFTP using shell script

Dynamically we are generating the shell script in the Application Engine Program as below and executing the shell script to place a file to other server.

ftp -vni << EOF
prompt off
open citadel.xxxx.xxx
user {USERID} {PASSWORD}
cd /Out/iapofac2/
put PSFIN PATH/FILENAME TARGET FILENAME
close
EOF

Now we have update the above script to SFTP since FTP is no longer supported. So can you please help us with the correct syntax need to written in the Shell script for SFTP