“Free Office product keys” are a trap — you pay with security, stability, and ethics. Microsoft does not offer legitimate free keys for Office 2021. If you cannot pay, use LibreOffice or the free web version of Office. Do not install any “activator” or “keygen.”

Microsoft Office Home & Student 2021 is a "one-time purchase" productivity suite designed for students and families who prefer to avoid monthly subscription fees. While "free" product keys are frequently advertised online, these are generally illegitimate and carry significant security risks.