The bathroom sink works and the bath but the kitchen sink and the shower doesn't have any hot water pressure it only drips?

What's the brand name of the shower valve? How old is it? Back to you, Tom

It's a triton shower valve and its about 2 years old

the kitchen sink and the shower doesn't have any hot water pressure
Sounds like the valves have picked up some mineral build up.
The solution would be to shut the water off, remove the cartridge and check and clean the inlet ports, Now turn the water back on for a few seconds to flush out the supplies. Do this with each affected valve. Good luck, Tom