Here is your parts breakdown.
Replacement parts for WHIRLPOOL KSRS25CKWH01 | AppliancePartsPros.com

First confirm that the compressor is running. You should be able to hear it and it should be vibrating. Since it is hot it does sound like it is running. It is probably overly hot because it is running constantly.

Check that the fan in the freezer is also running when the compressor and it's fan are on. If not that could be your problem.

Next remove the evaporator cover in the freezer so you can see the coils.

If there is no frost on them or just frost in one area then you have a sealed system problem.
No frost - out of freon, compressor is toast or blockage in the tubing.
Frost in one area - low on freon.

If either of the above, it will be an expensive repair as you will need a pro and there is no guarantee they can fix it. Often it is better to put the dollars towards a new unit.

If the coils are heavily frosted/iced up, you probably have a defrost problem.
The evaporator cannot pull air through the coils to cool it so it does not freeze properly.