There is a chamfer and fillet command in the sketch toolbar.
If the sketch has a chamfer or fillet in it then yes, you can edit them in the sketch.
If the chamfer and fillet is a feature then you have to edit the feature.
Mr McFadden i need to edit the chamfer and fillet in sketch after finish it .because after the finish the command and colse it in sketch you can not edit it
Just double click the feature in the FM to expose the dimensions in the graphics area, then double click any sketch dimension to access the Edit Dimension box.
Expand the feature in the FM, select either the feature or the sketch and select the Edit Sketch icon. Change dimensions to suit.
Per what Kelvin mentioned you can plus out the feature in the feature manager.
Oer another way is if you right click on the annotations in the feature manager and select "Display
annotations" then "show feature dimensions" the dimension will show up and you can double click on it
and edit it there as well. If you go this route you will probably have to regen.