Top bunk storage fastening

New to otr, solo. What's a good way to tie down all my crap laying on top of the unused upper bunk bed.
Had a sealed plastic gallon of water fall and Crack open spilling water everywhere. Other shit have fell forward and down.

Can anyone link to items to buy?
I have a 2019 freightliner cascadia.
Pic of an unused thingy for hooking:
I'm retarded about these things, help. I seen some bungie cords with hooks, but a net would be nice and for it to be tight so it just doesn't drop the shit on the floor still.

Thx!!