In any stage of chronic kidney disease the patient got erectile dysfunction and general itching ?

Those are often observed in advanced chronic kidney disease (stage 4 and 5, i.e. GFR less than 30 cc/min), but sometimes earlier. Medication(s) may be contributory to ED in early stages.

Depends on the duration and degree of the disease. This usually happens in the later stages. But those symptoms might not be related also. So a good exam by an MD is recommended.