So my nephew tripped over the cord while I was playing my ps4 and made my ps4 fall to the ground and now it says no USB storage device help?

he probably caused the hard drive heads to crash. $150 or so to repair unless they allow you to put in normal hard drives. then it's half that. if he damaged the solder points on the connectors, that will still cost about $50 to fix (not because it's hard to do but because so relatively few people know how to do it). maybe just remove then reinsert the drive.

Time to get it fixed.

just take it somewheres to get it fixed, and be thankful your nephew didnt hurt himself when he tripped over the cord

So what all was plugged into the PS4 and what cord did he trip over?

If you had a USB drive plugged into the PS4 and that fell to the floor, there's a chance the drive and/or the electronics in the drive were damaged by the fall.

If you think the drive itself is still OK, you can try to remove the drive from the enclosure, put it into a new enclosure, and plug that into the PS4. If you're lucky, the this will work. (the electronics in most USB enclosures is pretty fragile, even though the drive itself is far sturdier.)

However there's no guarantee this will work, meaning you'll have to buy a whole new external USB hard drive, and redownload or re-install your games onto it. Any save files that were on the hard drive and were not being backed up to the cloud, are gone.