This form is only for taxpayers who are claiming the premium tax credit. The premium tax credit occurs when your insurance company (the Marketplace) receives a payment on your behalf to cover your monthly premiums.
If it's been paid on your behalf, Form 8962 is a reconciliation of what was paid and what it actually cost.
Not everyone has to file Form 8962; only those taxpayers who are insured by the Marketplace have to worry about the form.