Create a Fillet or Chamfer

Use the Edit > Reshape > Fillet/Chamfer command to fillet or chamfer the intersection of two straight lines or walls, or the corner(s) of a polygon element.
Choose the Edit > Reshape > Fillet/Chamfer command, or
Fillet joins the endpoints of two straight segments endpoints with an Arc.
Chamfer joins the endpoints of two straight segments with a straight segment, cutting off corners.
Note: If filleting the arc with the current radius would extend any of the neighboring vertices, the radius will be limited automatically so that the filleting arc contains the closer neighboring vertex.
Click OK.
Note: The Fillet, Chamfer and Intersect commands are not effective on grouped elements, unless Suspend Groups is on.
Note: This checkbox is applicable only if the selected element is a polygon.
If you have selected a polygon and then the Edit > Reshape > Fillet/Chamfer command, the checkbox is selected by default and uneditable; the fillet/chamfer will apply to all nodes.