I have severe heart disease, malformations of my heart chromosomal abnormalities, cognitive impairments, marfan syndrome in my family, mental illness, can i be exempt from the vaccination? if so, how?

Exempt ? Why ? You mention no defect in your immune system or other reason a vaccination would be dangerous or ineffective. If you function well enough to make your own decisions you can get the vaccine or not. It remains a personal choice. Some private employers may choose to require it at which time it may be a legal issue, not one we can help you with.

From your description, you have chronic illness which is a risk factor for complications with COVID 19 infection. Please check with your local PCP and health department online, but vaccination is recommended.

The vaccination is recommended for people with comorbid conditions; It is also recommended for people receiving immunosuppressive medications including organ transplant recipients. If your place of employment requires immunization, you will want to discuss with your primary care provider if you can be exempt. As presented, this may be difficult.