Thank you for posting your query at DoctorSpring.com
I have noted your father's symptoms. Based on that, he has most probably suffered from brain stroke, where the blood supply to one part of brain gets reduced. The affected side in brain would be opposite to that of the weaker side. For example, if his right side of body is weak, then, the problem would be in the left side of brain.
The diagnosis of brain stroke can be confirmed by doing a brain scan, such as CT or MRI scan.
Please take him to the emergency room and get the brain scan.
Treatment can be started after seeing the brain scan report.
Blood sugar and blood pressure should be kept under control.
I hope it helps.
Dr. Sudhir Kumar MD (Medicine), DM (Neurology)
Senior Consultant Neurologist