I can see from the image that you posted that you have found the script step to send an email. There are lots of developer enhancements that you can use such as a global field for the subject line and text body if everyone will get the same message.
I think your stumbling block is the notion of "looping" through the contact records, sending an email at each stop along the way.
Also, you will create a calc field (might name it e_bodyCalc) which will be a text result and look something like:
"Dear" &" "& Contact Management::First Name
&"¶"& g_Body (the global message field)
Take a look at the Loop script step in help and it might become clear.
If later you still need help, come back and post your script and OS / version etc. and folks will help.
Many thanks for the tip! I'll give that a try and let you know.