How can I change a scripted ftp upload to lftp for High Sierra? I am very new to coding/scripting..

I have a noob question I guess:

I have this script to upload and delete files on my remote host:

#!/bin/bash

echo Starting Website upload ...
echo This may take some time depending on your internet connection ...
echo Waiting for remote connnection ...

/usr/bin/ftp -d server121.web-hosting.com &lt;&lt; ftpEOF

    prompt
    cd public_html
    delete index.html
    cd images
    mdelete *.jpg
    cd ..    
    lcd /Applications/PlexEmail/streamnet/
    put index.html
    lcd images
    cd images
    mput *.jpg
    bye
ftpEOF

echo Website upload successfull ...


Ok so now I upgraded my mac to high sierra 10.13 and there is no ftp command anymore.

Can please someone help me out to get this to work with lftp?
From looking at the lftp man page it seems as if lftp is scriptable. Something like the following should work (untested):

# upload script (save as website-update.lftp)
open server121.web-hosting.com
cd public_html
lcd /Applications/PlexEmail/streamnet/
put index.html
cd images
lcd images
mrm *.jpg
mput *.jpg
exit


And then use

lftp -f website-update.lftp


to execute it.

PS: lftp also has a mirror command which would this make even easier, probably.