At your Kendis program board, you are able to configure the milestones with the description and the target dates. It's a bit of a workaround to get the milestones visualized at the Kendis board. Here are the steps to follow.
Go to "Settings" on the left panel and select "Additional Card Types" (you need to be Super Admin to view these settings)
Create a "Milestones" card type if doesn't exist already
Now come back to your Kendis board
Open the Edit Board Settings view and select Teams
Check if you have already "Milestones" team from "Add Existing Team" link and if not then create a new team
Set the name as "Milestones" and prefix as "M" (this is just an example, you can rename it differently)
Important: Don't sync this team to Jira or AzureDevOps.
Move this team to the position you prefer, e.g., at the top of the board.
Now at the mainboard, create a new card from the bottom left green + icon
Type the milestone name, select date, and select the card type as "Milestones" (created in the first step)
Move this milestone card to the team
You can also create sub-items under this milestone by clicking on the "Add story" button.
Once the milestones are created, you can filter them if needed by clicking on the search and under "More Filters", select "Card type" and select Milestones.