Can my boss share personal information about me with other employees or can he ask me for detailed information on my medical condition?

You could file a lawsuit for invasion of privacy against the boss.  Invasion of privacy in this case is the public disclosure of private facts which occurred when he disclosed information about your unemployment benefits and medical records to other employees.

Your lawsuit for invasion of privacy could also include a separate cause of action (claim) for negligent infliction of emotional distress.  Negligence is based on the exercise of due care (that degree of care that in this case a reasonable employer would exercise under the same or similar circumstances to prevent foreseeable harm by maintaining the confidentiality of your medical and unemployment information).  Your boss had a duty to maintain the confidentiality of your unemployment and medical information as a reasonable employer would have done.  A breach of that duty occurred when the information was disclosed to other employees.  In addition to breach of the duty of care, you will need to prove actual cause and proximate cause to support your claim for negligent infliction of emotional distress.  Actual cause means but for the disclosure of your medical and unemployment information, would you have suffered emotional distress?  If the answer is no, actual cause has been established.  Proximate cause means were there any unforeseeable intervening acts which would relieve your boss of liability?  If the answer is no, you have established proximate cause.  Your lawsuit should name the boss as a defendant and also the company.

You will need to file your lawsuit prior to the expiration of the applicable statute of limitations or you will lose your rights forever in the matter