I need to create a script that shows the last login in a windows on the finder

You can use the last command in Terminal to list the last sessions of specific users. As for showing the information in the Finder, you can use Jamf  Helper to display the list to users.

I use this EA to get lasted logged in user

https://github.com/and992/Jamf-EA/blob/main/Last%20Logged-In%20Use.sh

I would probably use Jamf Helper, calling the script with a Launch Agent to display the info you want with the action buttons you desire. Assuming you are wanting the user to see this which is seems like you are wanting.