In the message editor, there is an Add placeholder dropdown menu from which you can find all the fields that can be personalized according to the recipient in the newsletter content.
The fields are visible in the text section with the name of the field between $ signs, for example $firstname$. If the recipient doesn't have any information in the field, this part will show an empty space in the message that is delivered to them, for example "Hey ,", when for other recipient it shows "Hey Annie,".
In addition, on the Segments page, add a condition for the property to the segment used in automation, for example "Property = firstname", "Condition = is", "Value = exist"
In the example below, tender_offer-amount (the amount of money offered for a product in auction) has been added to the newsletter. As in the example above, the text in the newsletter also includes the field name $tender_offer-amount$
If you want to send a personalized message from the LianaMailer tool and you want to use the variables in LianaAutomation, read instructions from here in the section Text personalization when the feature is retrieved through LianaAutomation.