I do not see the sense of this as the sequence of tracks depends on the sorting criteria you apply.
You can use the Numbering wizard to renumber the field TRACK.
You can create a user-defined field that has the contents of %_counter%. But user-defined fields are ignored by most players.
But as I said: this reflects only a snapshot of the current sorting criteria for the list.
You can modify the sequence in the list by dragging a file with ALT- to a new position.