Agree with JMS. New sprockets.
Those are the funny clamp on hubs, you take the three bolts out, and you screw 2 of them back into the threaded holes on the sprockets. This drives the tapered hub apart, and everything pulls off real easy.
If you don't realize this and try to force them off, pull thrm off, or heat them off, you might end up with that washer end mess the guy has on the bottom front one there. I would not be comfortable with whatever is going on there.
Sadly those tapper hubs are spendy, but I suspect that one is in bad shape and he cobbled together that 'repair' with the center bolt added and all the washers....
That short chain is too loose, you will need new chain and new sprockets. And whatever is going on with that one hub....
Those bearings like to go out, be sure behind everything the bearings are in good shape, could be part of the problem too.