The water pipe of my dishwasher?

Under normal circumstances this would not get clogged.

Two things I can think of ……

The water supply has been shut off recently, and the valve failed when it was reopened, ….or someone has shut the water supply off to the DW.

The valve should be located under the sink normally a 3/8” copper tubing coming off of the hot water line that goes to your sink; counter clockwise is open, clockwise is closed, unless you have a ball valve (not very common} In that case the handle should be parallel to the supply line to the dishwasher for open.

One thing you might check first …… see if the float is stuck

This is located inside the dishwasher many times towards the front, shape and size can vary but it be about 3” in diameter {like an upside-down can} generally made of the same material as the inside of the dishwasher. Wiggle it a bit to loosen it ….try starting dishwasher again at the very beginning of cycle. Cycle should begin with the pump for about 30 seconds then you should hear the solenoid for the water open up and water coming in.