The regions are the locations in which your instance will exist at. There are many regions available depending on your choice on the initial instance creation.
In total there are 6 regions spread across
3 physical locations. 6 physical locations.
The datacenter locations can be found at datacenter.
These legacy regions are available on legacy projects.
New projects will have the new regions available.
For these regions in the location of “3” will allow you to create the new instance types under new projects.