@nokturne213 To move a node, one need only drag can drop it, or press M to move it. It will not move if you only change the address tags. But if it moved quite far, you may want to retag the original node with whatever it has there now (or as a vacant shop if it is vacant,) and then make a new node at its new location.
@nokturne213 You can right click the building and “extract” the shop from the building. You should probably move the address information back onto the building, though.