https://www.openstreetmap.org/node/6504395454 

https://wiki.openstreetmap.org/wiki/Notes
Notes is a core feature of the OpenStreetMap.org website. It enables you to add a comment on the map to assist others in mapping/editing OpenStreetMap. Other users can respond to your notes, for example to ask for additional details if necessary.
Please do not use notes for general discussion or storing information not otherwise used in OpenStreetMap.
Use this feature to report an error in the data or to give some additional information, for instance the name of a street or an address etc.
Don't use notes for yourself in a way which is useless to others. Although you can use notes as a reminder to yourself, you are also inviting others to look at it. Descriptions must make sense to other people.

Sharing a link to the maps
https://wiki.openstreetmap.org/wiki/Browsing#Adding_a_Marker