1

How do we reposition a pin

2

Could you give a link with it, so we have some context what exactly do you mean?

3

Yes - https://www.openstreetmap.org/note/1424478
The point should actually be at 43.0252666, -96.62805 where a historic marker stands.

4

This is not the real marker, see here how to move and export link with arbitrary positioned marker:

https://wiki.openstreetmap.org/wiki/Browsing#Adding_a_Marker

5

As Kocio noted “notes” are not markers. Notes are used for indicating mistakes in the map.
You can create links pointing to 1 position (marker) on the map.
If you need more markers to show up at the same time, you should consider using something as http://umap.openstreetmap.fr

It would even be better that you map all the items that are visible today. Maybe there are information boards, memorials etc that can be added to the map.

6

Also, the note seems to be asking to map a historical use of the land. OSM is not a historical map. Whilst you can map memorials that actually appear on the ground, you cannot map a historical site for which there is no evidence on the ground. For memorials, you should map them as memorials not as the thing being remembered.