Hi,
As you have found out, water and electronics and electricity are not a good mix.
The water causes corrosion and provides circuit paths for the electricity which were not in the camera's operating design and could damage the components.
Rice is good to eat but does nothing to fix the problems caused by corrosion.
Don't Put Your Device in Rice. Here's Why
First do not turn on your camera and then you need to with the camera turned off, remove the battery as soon as possible from the camera to minimize further damage.''
Then you need to dis-assemble the rest of the camera and clean all the affected parts using Isopropyl Alcohol 90%+ to remove all traces of corrosion and water. Do not use "rubbing alcohol" as in some cases this is only 70% and is not as effective. If you do check the label to verify the amount
Here is a link that describes the process.
Electronics Water Damage
You may have to replace the battery as it is very hard to recover a battery from water damage.
As always with electronics, especially surface mounted PCBs be gentle when handling and especially when brushing away the corrosion. You do not want to remove any components from the board.
Hopefully after you have done all this the camera might possibly work correctly again.
Here is a link to the ifixit guides on how to repair your camera.
Samsung WB2100 Repair
If this process seems too daunting, take your camera to a reputable, professional camera repair service and ask for a quote for a repair. If you decide to do this, do it sooner than later.