how can I add the infobox o tittles to the markes creating by the block “create marker”

Hello community I need your help. Im developing an app that users can save locations ( latitude, longitude) using a marker. Also the user are be able to add a description of the place. All the information is stored in firebase. the issue is how can I add the infobox o tittles to the markes creating by the block “create marker”

Any suggest