In the Video / Project editor, go to the section that contains your media (timeline at the bottom).
Hold Shift on your keyboard.
Click each clip you want in the selection.
With multiple clips selected, you can:
Rearrange – drag clips into the order you want.
Delete – remove all selected clips at once.
Tips
Use multi-select when you need to reorganize many clips quickly.
Double-check before deleting—bulk deletes may not be reversible.
Combine this with layouts and animations to adjust a section faster.