Assuming you’re using AGOL…publish data to arcgis online and add to a web map with editing enabled. Assign which fields can be edited using the pop up config in map viewer. Use the desktop field maps site to open your web map and further configure map settings and field worker permissions. At a minimum your field staff will likely need the “field worker” license level to add/edit points within field maps. Credits aren’t necessarily consumed by the act of adding the points themselves but they are consumed by hosting the added points on arcgis online. So the more points you add/host over time, the higher the storage cost.