Move the clips to a folder on the PC, then load them in the Videopad bin (top-left).
Clips in the bin can be trimmed by using the SET START | SET END buttons under the preview window. Then use the ADD button to move the clip to the timeline.
Or build the sequence by dragging those clips to the timeline or right-click on one and use a PLACE choice from the drop-down menu.
Don't delete or move the source clips or VP won't know where to find them.
During editing, Save Project File AS routinely, giving it a unique # and name, so as to not overwrite prior saves. Using Save Project will overwrite.

If you make a mistake during editing immediately press <ctrl-Z> to backtrack, step-by-step. Same as EDIT | UNDO.