Indeed there is not enough information to understand what you are trying to do. But there is no separate map add-on.
If you want to display a map with a point shown as a little flag, you need to use Map Pages | openHAB.
If you want to define a property to select a lat/lon coordinate from a map use
- context: location
description: Map location picker
label: M-7 Location
name: location
required: false
type: TEXT
groupName: input
If you want to show a map with markers I think you need to define it as a page and then show that page in a card. See this post which shows the approach for a chart but should work for map pages too. [SOLVED] Main UI: Show/Call/Raise chart from Layout page - #2 by JustinG