None of what you posted is correct.
https://www.ontario.ca/page/vaccines-children-school
"
Unless they have a valid exemption, children who attend primary or secondary school must be immunized against:
- diphtheria
- tetanus
- polio
- measles
- mumps
- rubella
- meningitis (meningococcal disease)
- whooping cough (pertussis)
- chickenpox (varicella) – required for children born in 2010 or later
See the full list of recommended immunizations for your child.
Employers can ask for medical information, it is the employees right to refuse or permit the employer to contact the employees GP.
But any medical condition that could be a liability issue to the employee, coworkers or company should be disclosed.
https://www.lawnow.org/privacy-and-medical-information-in-the-workplace/
Basically it is like this:
" Employees have the right to keep their medical information private. But in order to be accommodated in the workplace, they are required to provide relevant medical information. Employers have a duty to accommodate employees to the point of undue hardship, therefore they have a right to seek medical information when necessary."
https://www.ontario.ca/document/your-guide-employment-standards-act/termination-employment
"The ESA does not require an employer to give an employee a reason why his or her employment is being terminated.
In most cases, when an employer ends the employment of an employee who has been continuously employed for three months, the employer must provide the employee with
either written notice of termination, termination pay or a combination (as long as the notice and the number of weeks of termination pay together equal the length of notice the employee is entitled to receive)."