Open the folder where you want to copy a file or folder. Select the object by clicking the mouse or move the selection with the keys-arrows. Then copy the object to the clipboard.
The copy is performed by the key combination “Ctrl-C pressed at the same time. There are other ways: click the "Properties" between the right keys "Alt" and "Ctrl". In the context menu select "Copy". This same menu appears when right-clicking on the mouse (click on the object).
Open the destination folder. Make sure that the same object (file or folder) belongs to the same type and has the same name. Otherwise, the object will be copied to the folder without replacement.
Insert the object in the destination folder. There are at least three options: the simplest is a combination of "Ctrl-V", a Little more time is pasting via the context menu (click "Properties" in the absence of selected files, or the right mouse button on blank space of the folder and select "Paste").
In the dialog box depending on the type of system or confirm the fact of substitution (the "Yes" button) or from the options choose "Copy with replacement".