How to split water current
You can get a "Y" adapter for a water hose connection like this one:



Image from this Amazon product.

Additional fittings could be used if your dishwasher needs something other than water hose threads.  When selecting a splitter such as this, try to find one that is solid brass and labeled for use with hot water.  Valves that contain plastic may not be rated for hot water, so be very careful with them.