An edit point is where one clip or image or photo ..changes to the next one
Seems that you have marked your beat points already with markers. Right?
Now you need to adjust the "edit points" so they fall on or close to the beat.
Sometime it works exactly on the beat...sometimesslightly ahead or behind. ( art of the editor)
Drag the ends of the clips ( whatever) to the markers.
You will need to do a bit of a bone up on how edits and different" trim modes" work.